Page 390 of 470

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 speci ed 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 in ated and not
overloaded. Excessive speed, underin ation, 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.
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.
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Page 391 of 470

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 5-69for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can’t know how it’s been used
or how far it’s been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
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Page 399 of 470

Removing the Flat Tire and
Installing the Spare Tire
If the wheel has a center cap, use the handle of the
folding wrench to pry it off. Then, with the other end of
the folding wrench, loosen the nuts.
If your vehicle has the plastic bolt-on wheel covers,
loosen the bolts completely using the folding wrench,
and remove the wheel cover.Once the center cap and/or wheel cover are removed,
use the following steps to remove the at tire and install
the spare tire.
1. Loosen the wheel
nuts – but do not
remove them – using
the folding wrench.
Turn the handle about
180 degrees, then
ip the handle back to
the starting position.
This avoids taking
the wrench off the lug
nut for each turn.
For wheels with a wheel lock key, use the wheel
lock key between the lock nut and folding wrench.
The key is supplied in the front passenger door
pocket.
Notice:If your vehicle has wheel locks and you
use an impact wrench to remove the wheel nuts, you
could damage the lock nut or wheel lock key. Do
not use an impact wrench to remove the wheel nuts
if your vehicle has wheel locks.
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Page 401 of 470
4. Attach the folding
wrench to the jack, and
turn the wrench
clockwise to raise the
jack head 3 inches
(7.6 cm).
5. Raise the vehicle by turning the folding wrench
clockwise in the jack. Raise the vehicle far enough
off the ground so there is enough room for the
compact spare tire to t under the wheel well.
6. Remove all the wheel nuts and take off the at tire.
{CAUTION:
Rust or dirt on the wheel, or on the parts to
which it is fastened, can make the 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
the 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 you need to, to
get all the rust or dirt off.
7. Remove any rust or dirt
from the wheel bolts,
mounting surfaces
and spare wheel.
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