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10-1. Specifications
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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 a 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.
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Traction AA, A, B, C
The traction grades, from highest to lowest, are AA, 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 (straight
ahead) traction tests and does not include cornering (turning) traction.
Temperature A, B, C
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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.
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 represent higher levels of performance on the laboratory test
wheel than the minimum required by law.
Warning: The temperature grades for this tire are established for a tire that is
properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading, either separately or in com-
bination, can cause heat buildup and possible tire failure.
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