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 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 Grades
The Traction grades, from highest to lowest, are AA, A, B, and C
.
These 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
.
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 characteris-
tics
.
Temperature Grades
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 con-
ditions 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 vehicle tires must meet under the Federal Motor Vehicle Safety Standard No
.
109
.
Grades B and A represent higher levels of performance on the laboratory test
wheel, than the minimum required by law
.
WARNING!
The temperature grade for this tire is established for a tire that is properly inflated and
not overloaded
.
Excessive speed, under-inflation, or excessive loading, either separately
or in combination, can cause heat buildup and possible tire failure
.
MAINTAINING YOUR VEHICLE
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