U.S. Department of
Transportation Tire quality
grades:
The U.S. Department of
Transportation requires Ford
Motor Company to give you the
following information about tire
grades exactly as the government
has written it.
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 1 ½ 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
WARNING
The traction grade assigned
to this tire is based on
straight-ahead braking traction
tests, and does not include
acceleration, cornering,
hydroplaning or peak traction
characteristics.
The traction grades, from highest
to lowest are AA, A, B, and C. The
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.
Temperature A B C
WARNING
The temperature grade for
this tire is established for a
tire that is properly inflated and
not overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
The temperature grades are A
(the highest), B and C,
representing the tire’s resistance
to the generation of heat and its
ability to dissipate heat when
tested under controlled conditions
on a specified indoor laboratory
test wheel. Sustained high
temperature can cause the
material of the tire to degenerate
and reduce tire life, and excessive
temperature can lead to sudden
tire failure. The grade C
corresponds to a level of
performance which all passenger
car tires must meet under the
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Ford GT (CGX) Canada/United States of America, enUSA, First Printing
Wheels and Tires
