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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. It should be noted that
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 might need to be checked. If you notice your
vehicle vibrating when driving on a smooth road, the tires
and wheels might need to be rebalanced. See your
dealer/retailer 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. Some aluminum wheels can
sometimes be repaired. See your GM dealer/retailer if
any of these conditions exist.
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Your GM dealer/retailer 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,
wheel nuts, or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts, wheel nuts, and TPMS sensors
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
CAUTION: (Continued)
CAUTION: (Continued)
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.
If your vehicle is a professional model, the wheels have
a unique offset and bolt hole diameter. Each of the
wheels on the professional vehicle have eight wheels
nuts. The wheels on the non-professional vehicle
have ve wheel nuts. SeeChanging a Flat Tire on
page 5-74for more information.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on the 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
CAUTION: (Continued)
CAUTION: (Continued)
damage to the brakes, suspension or other vehicle
parts. The area damaged by the tire chains could
cause you to lose control of the 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 the
vehicle and tire size combination and road
conditions. Follow that manufacturer’s instructions.
To help avoid damage to the vehicle, drive slowly,
readjust or remove the device if it is contacting the
vehicle, and do not spin the vehicle’s wheels. If
you do nd traction devices that will t, install
them on the front 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 creates 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. If a jack
is provided with the vehicle, it 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. If a jack is provided with
the vehicle, only use it 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 the hazard
warning ashers. SeeHazard Warning Flashers on
page 3-6.
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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 P (Park).
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 the vehicle has a at tire (B), use the following
example as a guide to assist you in the placement
of wheel blocks (A).
A. Wheel Block
B. Flat Tire
The following information explains how to use the jack
and change a tire.
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Removing the Spare Tire and Tools
The equipment needed is in the trunk. To access
the equipment:
1. Open the trunk. SeeTrunk on page 2-13for more
information.
2. Press the area at the
front of the handle
located on the cover
so that the back edge
raises.
3. Grab the handle and
remove the cover.4. Turn the wing nut to remove the retainer that holds
the wrench and jack.
5. Remove the wheel wrench, jack and spare tire from
the trunk. SeeSpare Tire on page 5-85for more
information.
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The tools to be used are the jack (A) and the wheel
wrench (B).
Removing the Flat Tire and
Installing the Spare Tire
1. Do a safety check before proceeding. SeeChanging
a Flat Tire on page 5-74for more information.
2. For models having aluminum wheels with a center
wheel cover, use the at end of the wheel wrench to
gently pry the wheel covers off. Store the wheel
cover and lug nut caps in the trunk until you have the
at tire repaired or replaced. Be careful not to scratch
the aluminum wheel edge and do not try to remove it
with your hands. Then loosen the wheel nuts with the
wheel wrench. Do not remove them yet.
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3. For models with exposed lug nuts, loosen them using
the wheel wrench. Do not remove them yet.4. Find the jacking location from the diagram above
and use the corresponding cutouts located in the
plastic molding.
The front location is (A) 8.5 inches (21 cm) from the
rear edge of the front wheel well, and the rear
location (B) is 3.5 inches (8.5 cm) from the front
edge of the rear wheel well.
The notches may also be labeled JACK with an
arrow pointing to the jacking location on the vehicle.
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