After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the tire and loading
information label. SeeLoading Your Vehicle on
page 4-28for an example of the tire and loading
information label and where it is located on your vehicle.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque” underCapacities and
Specifications on page 5-88.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if needed, to get all
the rust or dirt off. SeeChanging a Flat Tire on
page 5-64.
When It Is Time for New Tires
One way to tell when it is
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining.
You need a new tire if any of the following statements
are true:
•You can see the indicators at three or more places
around the tire.
•You can see cord or fabric showing through the
tire’s rubber.
•The tread or sidewall is cracked, cut, or snagged
deep enough to show cord or fabric.
•The tire has a bump, bulge, or split.
•The tire has a puncture, cut or other damage that
cannot be repaired well because of the size or
location of the damage.
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Buying New Tires
To find out what kind and size of tires you need, look at
the tire and loading information label attached to your
vehicle. SeeLoading Your Vehicle on page 4-28
for a label example and where it is attached to your
vehicle.
Make sure the replacements are the same size, load
range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.
{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes,
brands, or types (radial and bias-belted tires),
the vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes, brands, or types may also cause
damage to your vehicle. Be sure to use the
correct size, brand, and type of tires on all
wheels. It is all right to drive with your
compact spare temporarily, as it was
developed for use on your vehicle. See
Compact Spare Tire on page 5-73.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
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Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this may
affect the way your vehicle performs, including its
braking, ride and handling characteristics, stability and
resistance to rollover. Additionally, if your vehicle
has electronic systems such as, anti-lock brakes,
traction control, and electronic stability control, the
performance of these systems can be affected.
{CAUTION:
If you add different sized wheels, your vehicle
may not provide an acceptable level of
performance and safety if tires not
recommended for those wheels are selected.
You may increase the chance that you will
crash and suffer serious injury. Only use GM
speci c wheel and tire systems developed for
your vehicle, and have them properly installed
by a GM certi ed technician.
SeeBuying New Tires on page 5-59andAccessories
and Modifications on page 5-3for additional information.
Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
selection width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the Unites States National Highway Traffic
Safety Administration, which grades tires by treadwear,
traction and temperature performance. (This applies
only to vehicles sold in the United States.) The grades
are molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading system does not
apply to deep tread, winter-type snow tires, space-saver
or temporary use spare tires, tires with nominal rim
diameters of 10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements.
5-60
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course.
For example, a tire graded 150 would wear one and
a half (1
1⁄2) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction — AA, A, B, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades represent the tire’s ability
to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
Temperature — A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation of heat
and its ability to dissipate heat when tested under
controlled conditions on a specified indoor laboratory test
wheel.Sustained high temperature can cause the material of the
tire to degenerate and reduce tire life, and excessive
temperature can lead to sudden tire failure. The grade C
corresponds to a level of performance which all
passenger car tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades B and A
represent higher levels of performance on the laboratory
test wheel than the minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned and
balanced carefully at the factory to give you the longest
tire life and best overall performance. Adjustments to
wheel alignment and tire balancing will not be necessary
on a regular basis. However, if you notice unusual tire
wear or your vehicle pulling to one side or the other, the
alignment may need to be checked. If you notice your
vehicle vibrating when driving on a smooth road, your
tires and wheels may need to be rebalanced. See your
dealer for proper diagnosis.
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Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted
or corroded. If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle.{CAUTION:
Using the wrong replacement wheels, wheel
bolts, or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.
SeeChanging a Flat Tire on page 5-64for more
information.
5-62
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
Tire Chains
Notice:Use tire chains only where legal and only
when you must. Use only SAE Class “S” type chains
that are the proper size for your tires. Install them
on the front tires and tighten them as tightly as
possible with the ends securely fastened. Drive
slowly and follow the chain manufacturer’s
instructions. If you can hear the chains contacting
your vehicle, stop and retighten them. If the contact
continues, slow down until it stops. Driving too
fast or spinning the wheels with chains on will
damage your vehicle.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle’s tires properly.
If air goes out of a tire, it is much more likely to leak out
slowly. But if you should ever have a blowout, here
are a few tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
5-63
Storing a Flat or Spare Tire and
Tools
{CAUTION:
Storing a jack, a tire, or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision,
loose equipment could strike someone. Store
all these in the proper place.
To store a flat or spare tire, do the following:
1. Put the flat or spare tire in the compact spare tire
compartment, then secure the retainer.
2. Store the jack in its housing in the cargo area.
Secure the jack by turning the retainer clockwise.
3. Store the tools securely in the foam tray and place
the tray on top of the tire.
4. Replace the trim cover.
The compact spare tire is for temporary use only.
Replace the compact spare tire with a full-size tire as
soon as you can. SeeCompact Spare Tire on
page 5-73.
Compact Spare Tire
Although the compact spare tire was fully inflated
when your vehicle was new, it can lose air after a time.
Check the inflation pressure regularly. It should be
60 psi (420 kPa).
After installing the compact spare on your vehicle, you
should stop as soon as possible and make sure your
spare tire is correctly inflated. The compact spare is
made to perform well at speeds up to 50 mph (80 km/h),
so you can finish your trip and have your full-size tire
repaired or replaced where you want. Of course, it is best
to replace your spare with a full-size tire as soon as you
can. Your spare will last longer and be in good shape in
case you need it again.
Notice:When the compact spare is installed, do not
take your vehicle through an automatic car wash with
guide rails. The compact spare can get caught on the
rails. That can damage the tire and wheel, and maybe
other parts of your vehicle.
Do not use your compact spare on other vehicles.
And do not mix your compact spare tire or wheel with
other wheels or tires. They will not fit. Keep your spare
tire and its wheel together.
Notice:Tire chains will not t your compact spare.
Using them can damage your vehicle and can
damage the chains too. Do not use tire chains on
your compact spare.
5-73
Notice:If you drive your vehicle through an
automatic car wash that has silicone carbide tire
cleaning brushes, you could damage the aluminum
or chrome-plated wheels. The repairs would not be
covered by your warranty. Never drive a vehicle
equipped with aluminum or chrome-plated wheels
through an automatic car wash that uses silicone
carbide tire cleaning brushes.
Do not take the vehicle through an automatic car wash
that has silicone carbide tire cleaning brushes. These
brushes can also damage the surface of these wheels.
Tires
To clean the tires, use a stiff brush with tire cleaner.
Notice:Using petroleum-based tire dressing
products on your vehicle may damage the paint
nish and/or tires. When applying a tire dressing,
always wipe off any overspray from all painted
surfaces on your vehicle.
Sheet Metal Damage
If the vehicle is damaged and requires sheet metal repair
or replacement, make sure the body repair shop applies
anti-corrosion material to parts repaired or replaced to
restore corrosion protection.
Original manufacturer replacement parts will provide the
corrosion protection while maintaining the warranty.
Finish Damage
Any stone chips, fractures or deep scratches in the
finish should be repaired right away. Bare metal
will corrode quickly and may develop into major repair
expense.
Minor chips and scratches can be repaired with touch-up
materials available from your GM dealer. Larger areas
of finish damage can be corrected in your GM
dealer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, corrosion and rust can develop on the
underbody parts such as fuel lines, frame, floor pan,
and exhaust system even though they have corrosion
protection.
At least every spring, flush these materials from the
underbody with plain water. Clean any areas where mud
and debris can collect. Dirt packed in close areas of
the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can
do this for you.
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