Treadwear; Traction A B C; Temperature A B C - Ford 1996 Escort Manual

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 one and one-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 significantly from the
norm due to variations in driving habits, service
practices and differences in road characteristics
and climate.

Traction A B C

The traction grades, from highest to lowest, are
A, B, and C, and they 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.
Warning: The traction grade assigned to this tire
is based on braking (straightahead) traction tests
and does not include cornering (turning)
traction.

Temperature A B C

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 Federal Motor Vehicle
Safety Standard No. 109. Grades B and A
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