Uniform Tire Quality; Grading - Chevrolet 2011 Impala Owner's Manual

WARNING
If different sized wheels
are used, there may not
be an acceptable level of
performance and safety if
tires not recommended for
those wheels are selected.
This increases the chance of
a crash and serious injury.
Only use GM specific wheel
and tire systems developed
for the vehicle, and have them
properly installed by a GM
certified technician.
See Buying New Tires on
page 10 58 and Accessories
and Modifications on page 10 3
for 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
Vehicle Care
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.
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition
To These Grades.
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