{CAUTION:
If you use bias-ply tires on the 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 the
vehicle.
Vehicles that have a tire pressure monitoring system
could give an inaccurate low-pressure warning if
tires not recommended for your vehicle are installed.
Tires that do not match the original equipment tires
could give a low-pressure warning that is higher or lower
than the proper warning level you would get with
original equipment tires. SeeTire Pressure Monitor
System on page 5-59.
Your vehicle’s original equipment tires are listed on the
Tire and Loading Information Label. SeeLoading
the Vehicle on page 4-16, 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 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.
{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 5-64andAccessories
and Modifications on page 5-3for additional information.
5-65
Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum selection width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the Unites 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.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
1 2) 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.
5-66
