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{WARNING:
If you use bias-ply tires on the vehicle, the
wheel rim flanges 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
the 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.
Vehicles that have a tire pressure monitoring system
may give an inaccurate low‐pressure warning if
non‐TPC spec rated tires are installed on your vehicle.
Non‐TPC Spec rated tires may give a low‐pressure
warning that is higher or lower than the proper warning
level you would get with TPC Spec rated tires. SeeTire
Pressure Monitor System on page 6‑66.
Your vehicle's original equipment tires are listed on the
Tire and Loading Information Label. See Loading the
Vehicle
on page 5‑31, for more information about the
Tire and Loading Information Label and its location on
your vehicle.
Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this could
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, rollover
airbags, 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.
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Page 466 of 560

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 specified
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 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.
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WARNING: (Continued)
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, re‐adjust or remove the device if it is
contacting the vehicle, and do not spin the
wheels. If you do find traction devices that will fit,
install them on the rear tires.
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.
If a tire goes flat, the next part shows how to use the
jacking equipment to change a flat tire safely.
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