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CAUTION: (Continued)
Your vehicle may have a compact spare
tire and wheel assembly. If the vehicle
has a compact spare tire and wheel,
they have the same overall diameter
as your vehicle’s full-size tires and
wheels. Because they were designed
and developed for use on your vehicle,
it is all right to drive your vehicle with
the compact spare installed properly.
Compact spare tires are designed for
temporary use only. SeeSpare Tire
on page 420.
{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.
If you must replace your vehicle’s tires with
those that do not have a TPC Spec number,
make sure they are the same size, load range,
speed rating, and construction type (radial and
bias-belted tires) as your vehicle’s original tires.
Your vehicle’s original equipment tires are listed
on the Tire and Loading Information Label.
This label is attached to the vehicle’s center pillar
(B-pillar). SeeLoading Your Vehicle on page 293,
for more information about the Tire and Loading
Information Label and its location 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 392and
Accessories and Modi cations on page 324
for additional information.
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Uniform Tire Quality Grading
Quality grades can be found where applicable
on the tire sidewall between tread shoulder
and maximum section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National
Highway Traffic Safety Administration (NHTSA),
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
(UTQG) 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 and additional
General Motors Tire Performance Criteria (TPC)
standards.
Treadwear
The treadwear grade is a comparative rating based
on the wear rate of the tire when tested under
controlled conditions on a speci ed government
test course. For example, a tire graded 150 would
wear one and a half (1.5) 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 signi cantly 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 speci ed 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.
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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/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 (except some aluminum wheels, which can
sometimes be repaired). See your dealer/retailer
if any of these conditions exist.
Your dealer/retailer will know the kind of wheel
you need.
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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 400for more
information.
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.
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Tire Chains
{CAUTION:
If your vehicle has P225/75R15, P265/
75R15, P235/75R15, or P235/50R18 size
tires, do not use tire chains. They can
damage your vehicle because 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.
CAUTION: (Continued)
CAUTION: (Continued)
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,
readjust, or remove the device if it is
contacting your vehicle. Do not spin the
vehicle’s wheels.
If you do nd traction devices that will t,
install them on the rear tires.
Notice:If your vehicle has a tire size other
than P225/75R15, P265/75R15, P235/75R15 or
P235/50R18 use tire chains only where legal and
only when you must. Use chains that are the
proper size for your tires. Install them on the
tires of the rear axle. Do not use chains on the
tires of the front axle. Tighten them as tightly
as possible with the ends securely fastened.
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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 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.
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