/I CAUTION:
Mixing tires could cause you to lose control while
driving.
If you mix tires of different sizes or types
(radial and bias-belted tires), the vehicle may not
handle properly, and you could have a crash.
Using tires of different sizes may also cause
damage to your vehicle. Be sure to use the same
size and type tires on all wheels.
It’s all right to drive with your compact spare,
though. It was developed for use
on your vehicle.
Uniform Tire Quality Grading
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, 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 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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