
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, antilock brakes, traction
control, and electronic stability control, the performance
of these systems can be affected.
{WARNING:
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 specific wheel and tire
systems developed for your vehicle, and have
them properly installed by a GM certified
technician.
See Buying New Tires
on page 6‑74andAccessories
and Modificationson page 6‑3for additional
information.
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.
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All Passenger Car Tires Must Conform to Federal
Safety Requirements In Addition To These
Grades.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
government test course. For example, a tire
graded 150 would wear one and a half (1½) 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 significantly 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 specified
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.
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 specified indoor laboratory test wheel.
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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 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 inflated and not
overloaded. Excessive speed, underinflation,
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 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,
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.
{WARNING:
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.
See Changing a Flat Tire
on page 6‑90for more
information.
Used Replacement Wheels
{WARNING:
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.
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Tire Chains
{WARNING:
If your vehicle has P235/55R17, or P245/50R18
size tires, 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(Continued)
WARNING: (Continued)
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, and do not
spin your vehicle's wheels.
If you do find traction devices that will fit, install
them on the front tires.
Notice: If your vehicle has P225/60R16 size tires,
use tire chains only where legal and only when you
must. Use only SAE Class S‐type chains that are the
proper size for your tires. Install them on the front
tires and tighten them as tightly as possible with the
ends securely fastened. 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.
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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 flat tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
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.{WARNING:
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 flat 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 flat tire.
This vehicle may come with a jack and spare tire or a
tire sealant and compressor kit. To use the jack and
spare tire, follow the instructions below. To use the tire
sealant and compressor kit, see Tire Sealant and
Compressor Kit
on page 6‑82.
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If this vehicle has a tire sealant and compressor kit,
there may not be a spare tire, tire changing equipment,
and on some vehicles there may not be a place to store
a tire.
The tire sealant and compressor can be used to
temporarily seal punctures up to ¼ inch (6 mm) in the
tread area of the tire. It can also be used to inflate an
under inflated tire.
If the tire has been separated from the wheel, has
damaged sidewalls, or has a large puncture, the tire is
too severely damaged for the tire sealant and
compressor kit to be effective. SeeRoadside
Assistance Program on page 8‑8.
Read and follow all of the tire sealant and compressor
kit instructions. The kit includes:
A. On/Off Button
B. Selector Switch
(Sealant/Air or Air Only)
C. Pressure Relief Button
D. Pressure Gauge E. Air Only Hose
(Black)
F. Sealant/Air Hose (Clear)
G. Power Plug
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19. Stop at a safe location and check the tire pressure.Refer to Steps 1 through 11 under “Using the Tire
Sealant and Compressor Kit without Sealant to
Inflate a Tire (Not Punctured).”
If the tire pressure has fallen more than 10 psi
(68 kPa) below the recommended inflation
pressure, stop driving the vehicle. The tire is too
severely damaged and the tire sealant cannot seal
the tire. See Roadside Assistance Program
on
page 8‑8.
If the tire pressure has not dropped more than
10 psi (68 kPa) from the recommended inflation
pressure, inflate the tire to the recommended
inflation pressure.
20. Wipe off any sealant from the wheel, tire, and vehicle.
21. Dispose of the used sealant canister and sealant/ air hose (F) assembly at a local dealer or in
accordance with local state codes and practices.
22. Replace it with a new canister available from your dealer.
23. After temporarily sealing a tire using the tire sealant and compressor kit, take the vehicle to an
authorized dealer within a 100 miles (161 km) of
driving to have the tire repaired or replaced.
Using the Tire Sealant and Compressor
Kit without Sealant to Inflate a Tire
(Not Punctured)
To use the air compressor to inflate a tire with air only
and not sealant:
Always do a safety check first. See If a Tire Goes Flaton page 6‑81.
1. Remove the tire sealant and compressor kit from its storage location. See Tire Sealant and
Compressor Kit Storage on page 6‑90.
2. Unwrap the air only hose (E) and the power plug (G).
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