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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.
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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 5-78for more
information.
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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
{CAUTION:
Do not use tire chains. There is not enough
clearance. Tire chains used on a vehicle
without the proper amount of clearance can
cause damage to the brakes, suspension, or
other vehicle parts. The area damaged by the
tire chains could cause you to lose control of
your vehicle and you or others may be injured
in a crash. Use another type of traction device
only if its manufacturer recommends it for use
on your vehicle and tire size combination and
road conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, re-adjust or remove the
device if it is contacting your vehicle, and do
not spin your wheels. If you do nd traction
devices that will t, install them on the
rear tires.
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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 at tire will create a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout remove your foot from
the accelerator pedal. Get the vehicle under control
by steering the way you want the vehicle to go. It may
be very bumpy and noisy, but you can still steer.
Gently brake to a stop, well off the road if possible.{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a at tire.
If a tire goes at, the next part shows how to use the
jacking equipment to change a at tire safely.
Changing a Flat Tire
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your vehicle’s
hazard warning ashers. SeeHazard Warning Flashers
on page 3-6for more information.
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{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put the shift lever in PARK (P).
3. Turn off the engine and do not restart
while the vehicle is raised.
4. Do not allow passengers to remain in
the vehicle.
To be even more certain the vehicle will not
move, you should put blocks at the front and
rear of the tire farthest away from the one
being changed. That would be the tire, on the
other side, at the opposite end of the vehicle.When your vehicle has a at tire, use the following
example as a guide to assist you in the placement of
wheel blocks.
The following information will tell you next how to use
the jack and change a tire.
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Removing the Spare Tire and Tools
A. Retaining Bracket
and Wing Nut
B. Tool Kit and
Jack Tools
C. Wing Nut Retaining
Wheel BlocksD. Wheel Blocks
E. Jack
F. KnobA. Knob
B. Removable Storage Tray
C. Retaining Hook
D. Retaining Bracket
and Wing Nut
E. Tool Kit and Jack ToolsF. Mounting Bracket
G. Wing Nut Retaining
Wheel Blocks
H. Wheel Blocks
I. Jack Regular Models - Rear Access PanelExtended Models
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On the regular models, the equipment is located on the
driver’s side of the vehicle, behind the left trim panel
in the rear of the vehicle. Unlatch the release lever
to open the trim panel door. Skip the rst step and follow
the last three.
On the extended models, the equipment you will need is
under the storage tray on the driver’s side of the
vehicle, in the trim panel.
1. Remove the tray to access the tools.
2. Remove the wing nut used to retain the tool kit by
turning it counterclockwise.
3. Turn the knob on the jack counterclockwise to
release the jack from its holder and to lower the
jack head.
4. Remove the wheel blocks and the wheel block
retainer by turning the wing nut counterclockwise.
You will use the jack handle extensions and the
wheel wrench to remove the underbody-mounted
spare tire.A. Spare Tire (Valve
Stem Pointed Down)
B. Hoist Assembly
C. Hoist Cable
D. Tire Retainer
E. Hoist Shaft
F. Hoist End of
Extension ToolG. Hoist Shaft
Access Hole
H. Wheel Wrench
I. Jack Handle
Extension
J. Spare Tire Lock
(If Equipped)
1. Open the spare tire lock cover on the bumper and
use the ignition key to remove the lock if your
vehicle is equipped with a spare tire lock (J).
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2. Assemble the wheel wrench (H) and the two jack
handle extensions (I) as shown.3. Insert the spare tire
end (open end) (F)
of the extension
through the hole (G)
in the rear bumper.
Be sure the hoist end of the extension connects to
the hoist shaft (E). The ribbed square end of the
extension is used to lower the spare tire.
4. Turn the wheel wrench (H) counterclockwise to
lower the spare tire to the ground. Continue to
turn the wheel wrench until the spare tire can be
pulled out from under the vehicle.
If the spare tire does not lower to the ground, the
secondary latch is engaged causing the tire
not to lower. SeeSecondary Latch System on
page 5-89.
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