Slide 1

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 2

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 3

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 4

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 5

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 6

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 7

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 8

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 9

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 10

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 11

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 12

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 13

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 14

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 15

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 16

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 17

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 18

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 19

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 20

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 21

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 22

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 23

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 24

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 25

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 26

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 27

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 28

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.


Slide 29

Tires
How they work
Maintaining them
Inflation
Rotating & balancing
Checking tires
Alignment
Buying tires
Size
Mileage ratings
Changing a tire
Tire pressure monitoring
systems

Steering
How it works
Checking power steering
fluid

TIRE

WHEEL

The tires on your car are the only link between your car and the road. They are a lot
more than just pieces of rubber—they have been carefully designed to maintain
traction and contact with the road under all conditions. Making sure that your tires are
up to this task is your responsibility!
Treads

The treads on your tires are designed
to channel water and snow out from
under the tire so that the tire can stay
in contact with the road.
If the tire is not inflated correctly or is
worn too much, it will not channel
water away fast enough. This results
in hydroplaning or loss of control.
Obviously, tires are very important to
your safety. Yet, for most car owners,
tires are the most neglected item on
the vehicle. Don’t let your tires fall
into this category!

According to the National Highway Traffic Safety Administration (NHTSA), low tire
pressure-related crashes are to blame for 660 fatalities and 33,000 injuries every year. In
addition to this, Americans would save roughly 5 million gallons of gasoline every day if
everyone kept their tires inflated properly. If these statistics aren’t enough to convince
you, consider that the average driver could increase the lifespan of his or her tires by
40% by doing nothing more than maintaining the correct tire pressure!
If your tires are properly inflated, the entire tread will contact the road, resulting in better
traction, better fuel economy, uniform tire wear, and fewer accidents. Under-inflated tires
will wear more on the outside edges, while over-inflated tires will wear more in the middle
as shown:

As we learned in an earlier lesson, each automobile has an “ideal” tire inflation pressure. This
information is found on the “tire placard” that is usually found inside the driver’s door or inside
the glove box. Your owner’s manual should also have this information.
Can you find the recommended tire pressure on the placard shown below? Go to your car and look
for your tire placard!

•

•

People often mistakenly assume that their tires
should be inflated to the pressure shown on the
sidewall of the tire. This is only the maximum
pressure that this tire can withstand. Over- or
under-inflating your tires can cause poor traction,
rapid tire wear, low fuel economy, and even a
severe accident.
Always follow the pressure specifications on the
tire placard!

Worn on outside edges

Worn evenly across tire

Worn in the middle

These photos show a tire driving through water with different inflation pressures. This tire is
supposed to be inflated to 35 psi. You will notice that when it is properly inflated, the entire
tire contacts the road, but when it is underinflated very little road contact is made.

35 psi sitting still in water
35 psi at 60 mph
Good contact; the
tire disperses the
water well

If the tires do not disperse
water, a film of water remains
between the tire and the
road, causing a loss of
traction and vehicle control.

30 psi at 60 mph
Poor contact; the tire does
not disperse the water and
the dark areas show that
the tire is only contacting
the road on the very edges

25 psi at 60 mph

There are several reasons that tire pressure should be checked at least once a
month. Here are just a few:
•Even tires that don’t have leaks lose enough air each
month to drop about 1-2 psi in pressure
•For every 10° F change in temperature, tire inflation
pressure will change by about 1 psi
•For every 1 psi your tires are below the recommended
level, your fuel economy suffers by
approximately 0.4%
•Under-inflated tires get very hot while driving,
increasing the likelihood of a blowout
(which often results in a rollover)
•It is nearly impossible to tell if a tire has low pressure
by just looking at it; use a gauge

If your tires are under-inflated or over-inflated, they
will wear rapidly, costing you hundreds of dollars in
unnecessary tire purchases.

Keep a tire pressure gauge in your car
The easiest way keep your tire pressure in check is to buy an inexpensive pressure gauge
and keep it in your car. But don’t just keep it, use it often!
If you need to add air to your tires, many gas stations have an air compressor you can use

Tire pressure should be checked cold
This means that you should only check and set your tire pressure when the car has been
sitting still for at least three hours or has been driven less than 2 miles.

Check your spare tire, too!
Many people forget to check the pressure
of their spare tire until they need their
spare and discover that it is flat!
Your spare tire often calls for a different
pressure than your other tires. Check your
tire decal to find this information.
Return to I-learn now and watch the video
entitled, “Checking and Adjusting Tire Pressure.”

Each of the four tires on your vehicle wears differently. For example, because the front
wheels are constantly being steered back and forth, they tend to wear faster than the back
wheels do. Also, the front tires on a front-wheel-drive car and the back tires on a rearwheel-drive car wear at different rates because they “slip” on the pavement more often.
To get the most out of your tires, you want all four tires to wear at the same rate. To make
this happen, you should rotate your tires (or move them to a new position on the car)
every 6,000 miles.

You really don’t need to make an extra trip to the shop to get your tires rotated. Having
your tires rotated every 6,000 miles means that it can be done at every other oil change.
An added bonus—while the wheels are off, ask your service professional to check your
brakes. Since it requires very little extra work, they may do this at no charge!

There are many different patterns to choose from when deciding which tire to move
where. However, what matters the most is that the front tires get moved to the back and
the back tires get moved to the front at each rotation. If no rotation period or pattern is to
be found in your owner's manual, rotate your tires at least every 6,000 miles and follow
one of the patterns suggested here.

“Balancing tires” involves putting small weights on
the wheel to “offset” any heavy spots that might
otherwise cause a vibration when the wheel is
spinning. An imbalanced tire and wheel assembly
can result in a vibration that causes premature
wear of tires, struts, shocks and other components.

Most wheel and tire balancing today is done on a computerized balancer.

The typical symptom of a tire balance problem is a vibration in the steering wheel that is
very pronounced only at a certain speed. The vibration may go away or lessen as you
speed up or slow down. While this type of vibration can occur at any speed it is most
likely to occur at highway speeds.
Many people don’t wait for symptoms but have their tires routinely balanced at every
other tire rotation. This is really up to you!

In order to be considered safe and legal, all of your tires must have at least 1/16 inch of
tread on the entire tread area of the tire. This means that even if most of the tire is fine,
but one edge is worn too low, the tire should be replaced.
The penny trick: An easy way to check your tire tread depth is to use a
penny. Stick the penny into the grooves in the tire tread, Lincoln’s
head first. If all of his head sticks out above the tread blocks, on any
part of the tire, it is time to buy new ones.

This tire is worn beyond the legal
and safe limit of 1/16 inch. All of
Lincoln’s head is visible.

This tire is in very good condition. It
has plenty of tread depth and will
maintain good contact with the road.

Another way to determine the condition of your tire is to look for the wear indicator
bars; almost all tires have them. When the treads are worn down to the point that
they are even with any of the wear indicator bars, they are at the 1/16 inch limit.

The treads on this tire are worn to the point that they are even with the
wear indicator bars. This tire should be replaced.

What is wheel alignment? When a wheel alignment is performed, what happens is
exactly as it sounds—the wheels are aligned so that they all point in the same direction. If
any of the wheels on your car are misaligned by even a fraction of a degree, you may
experience problems.
What causes wheels to get out of alignment? There are three things that can cause this:

• Normal “wear and tear” on the suspension components
•Bent or damaged parts caused by hitting a pothole or curb, or because of a minor
accident
•Repair work to your car that involved replacing a steering or suspension
component
Usually, you cannot tell if your
wheels are misaligned by just
looking at them. However, there are
ways that you can know. They will
be discussed in the next few slides.

There are three different angles that have a major affect on your wheel alignment:
Camber

Caster

Toe

is the inward or
outward tilt of the wheel.
Ideally, the wheel should
be straight up and down.
However, many things
can cause it to lean in or
out too much.

is the forward or
backward leaning of the
steering axis. The
motorcycle shown below
has a lot of “caster.”

is the direction that
the wheels are pointed.
Obviously, we want all of
our wheels pointed in
the same direction—
straight down the road;
in the real world, a lot of
us may need to have our
“toe” adjusted a little!

A “camber” problem will cause the affected tire to wear rapidly on the edge that it is
leaning toward. It will also make the car “pull”—or want to drive to one side when you let
go of the steering wheel. If you experience either of these symptoms, get an alignment!

Caster is the angle that has the least effect on your steering and tire wear.
However, if the caster angle is bad enough, it can cause a slight pull to one side.

Zero Toe

Toe-in

Toe-out

If your front or back wheels are not pointed in the same direction as each other, the tires will not roll well down the
road—they will actually have to “scuff” down the road sideways. This is the most common alignment problem and is
the primary cause of premature tire wear. An incorrect “toe” condition won’t cause the car to pull to one side, but the
scuffing will cause the tires to wear with a “feathered” edge. To detect a feathered edge, run your hand across the
tread of the tire. If it feels smooth in one direction but rough in the other, you have a “toe” problem!
Slight
feathered edge

Extreme
feathered edge

Did you know?
If your toe angle is incorrect by as
little as 1/10 of an inch, the
scuffing that will happen to your
tire is equivalent to dragging your
tire sideways down the road
about 50 miles per year.

Generally, it is recommended that you have a wheel
alignment performed when you purchase a new set of
tires.
Realistically, you probably don’t need one if you don’t
notice any of the symptoms of wheel alignment
problems. If you notice any of the following problems,
you should have a wheel alignment performed as soon
as possible:

Uneven or excessive tire wear
The car pulls to one side (check tire pressure first; a low tire on one side will
also cause a pull)
A crooked steering wheel (when going straight down the road, your steering
wheel should be straight up and down)

Now, with all that you have learned about tire pressure and alignment, can you look at
these tires and identify any problems?

Click here for the answers!

There is a great variety of tires that will fit on your car. How do you know which one is best
for you? Hopefully the person who is selling you the tires can answer some of your basic
questions—but more importantly—hopefully you will know what questions to ask!
Tires with aggressive tread patterns are good in mud and snow, but may be very noisy
on the highway. You should try to find a tire that is a compromise and will give you the
benefits that are most important to you.
Tires have mileage ratings. They are rated for the
approximate number of miles the tire will last. If you
buy the cheapest tire available, it may only last you a
little more than a year. Most tires sold today are
rated for between 20,000 miles and 80,000 miles.

Different types of tires available

Tip: You should do everything you can to make sure
that your tires wear out evenly so that when it is time
to replace them, you can replace all four tires at the
same time. This is especially important in all-wheeldrive vehicles; all tires must be exactly the same
diameter. The key to this is rotating your tires!

Do you need snow tires in the winter? Snow tires (and studded snow tires)
are designed to have optimum traction in the ice and snow. However, if you
have all-season tires on your car that are in good shape, you probably don’t
need to buy snow tires. But before winter comes, make sure your tires are
in good shape; if they are not, replace them!

Studded snow tires

Have you read any good tires lately? Well, reading tires may not be much like reading a
good novel, but there is a lot you can learn from a tire.

While there is a great deal of information on the sidewall of a tire, perhaps the
most important numbers are the size and the date code.

SIZE:

The tire shown above is 185 mm wide, is 75% as tall
as it is wide, and fits on a 14 inch rim. You should never have
two tires of different sizes on the same car! Can you find this
information on your tires?

DATE CODE:

The tire shown above was
manufactured in the 27th week of 2004. A tire
that is more than 6 years old may be unsafe.
When were your tires made?

Optional Link: Click here to learn more about tires

Because flat tires are relatively rare today, many of us aren’t prepared for the event
that we might have one. Even though flat tires are rare, odds are likely that you will
experience many flats during your lifetime!
The time to prepare for this event is now!
If you get a flat tire, pull
over immediately (if it is safe
to do so). If you drive on a
flat tire for even a short
distance, the tire will be
permanently damaged and
will have to be replaced.
•Make sure that you know how to jack your car and change a tire
•Check and make sure that you have a jack and a lug wrench in your car
•Take your lug wrench out and make sure it fits all of the lug nuts on your wheels!
•Make sure that you have a spare tire and that it is properly inflated
•Read in your owner’s manual about specifics to your vehicle and your spare tire—remember that spare tires
are only for temporary use!

Return to I-learn now and watch the video entitled, “Changing a Flat Tire.”

If you have a tire that seems to always need
some air or seems to always get low faster
than your other tires, you probably have a
small leak in the tire.
Chances are good that you have a nail or screw
in your tire somewhere. If the problem isn’t
fixed, it may get worse and lead to a flat tire.
Nail

A leaking or flat tire can usually be fixed very
inexpensively. Just take the tire (or the
entire car if the tire is still on the vehicle) to a
repair shop.
If the leak or hole is in the tread area of the
tire, they can patch it for you. If the leak is
somewhere on the sidewall of the tire, it
cannot be repaired.

All 2008 and newer cars are required by law to have a tire pressure monitoring system.
Some cars have already used systems like this for years. Basically, each wheel has a
sensor in it that measures the pressure of the tire. The sensor then transmits a radio
signal to the computer in the car that displays a message if any of the tires is not
inflated properly.

Remember that just because you have a tire pressure monitoring system does not
mean that you don’t need to check your tires anymore! Your car does not have a
brain—you must use yours!

We probably have a pretty good idea of what our steering system does. It allows us to
drive, turn, and control our cars with ease. Steering systems require very little
maintenance. However, the one item that should be checked occasionally is the power
steering fluid. When you are under your hood checking your other fluids, take a moment
to check on this one:

To check your power steering fluid, find the reservoir,
remove the cap, and check the level. Some cars have a
dipstick attached to the reservoir cap, and others use
an opaque reservoir with “min” and “max” marks.

How a steering gear works

If you have to add fluid, look in your owner’s manual to
find out what type of fluid to add. Although you can
buy generic “power steering fluid,” it is not the best
choice for all cars.

All of us want to keep our cars on the road and
keep them going straight! We also want to get
our money’s worth out of our tires and steering
system.
In this lesson we learned how to make sure that
our tires and steering system are working
properly and will keep us safe while driving.
We have covered tires, how they work, and how
to take care of them. We also have learned how
a car owner can identify problems with the tires
by performing simple occasional inspections.
This lesson covered the routine maintenance and
service that car owners should have performed—
such as tire rotation and balance, wheel
alignment, and checking power steering fluid.