Uniform Tire Quality Grading; Mixing tires could cause you to lose control while; driving. If you mix tires of different sizes or types- Page 306

yellow

blue     

6-47

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.

CAUTION:

If you use bias

-

ply tires on your 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 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.