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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 226,
for more information about the Tire and Loading
Information label.
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 296and
Accessories and Modi cations on page 235
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 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.
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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 clearance to the body
and chassis.
{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 a crash. 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 you need to, to get all the rust or
dirt off.
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{CAUTION:
Never use oil or grease on studs or the
threads of the wheel nuts. If you do, the
wheel nuts might come loose and the
wheel could fall off, causing a crash.
{CAUTION:
Incorrect wheel nuts or improperly
tightened wheel nuts can cause the wheel
to become loose and even come off. This
could lead to a crash. Be sure to use the
correct wheel nuts. If you have to replace
them, be sure to get new GM original
equipment wheel nuts.Notice:Improperly tightened wheel nuts can
lead to brake pulsation and rotor damage.
To avoid expensive brake repairs, evenly
tighten the wheel nuts in the proper sequence
and to the proper torque speci cation.
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:
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.
If a Tire Goes Flat
Your vehicle has a tire in ator kit. There is no
spare tire, no tire changing equipment, and
no place to store a tire.
It is unusual for a tire to blow out while you are
driving, especially if you maintain your tires
properly. SeeTires on page 284. If air goes out
of a tire, it is much more likely to leak out slowly.
But, if you should ever have a blow out, 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 blow out, particularly on a curve, acts much
like a skid and may require the same correction
you would use in a skid. In any rear blow out,
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.
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