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Maintenance
Tread wear
The tread wear grade is a compara-
tive rating based on the wear rate of
the tire when tested under controlled
conditions on a specified govern-
ment test course. For example, a tire
graded 150 would wear one-and-a-
half times (1½) as well on the gov-
ernment 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
because of variations in driving
habits, service practices and differ-
ences in road characteristics and cli-
mate.
These grades are molded on the
side-walls of passenger vehicle tires.
The tires available as standard or
optional equipment on your vehicle
may vary with respect to grade.Traction - AA, A, B & C
The traction grades, from highest to
lowest, are AA, A, B and C. Those
grades represent the tires ability to
stop on wet pavement as measured
under controlled conditions on speci-
fied government test surfaces of
asphalt and concrete. A tire marked C
may have poor traction performance.
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 condi-
tions 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 cor-
responds 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 labora-
tory test wheel than the minimum
required by the law.
WARNING
The traction grade assigned to
this tire is based on straight-
ahead braking traction tests,
and does not include accelera-
tion, cornering, hydroplaning,
or peak traction characteristics.
WARNING - Tire
temperature
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
build-up and possible sudden
tire failure. This can cause loss
of vehicle control and serious
injury or death.
