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Maintenance
can be carried by the tire. When
replacing the tires on the vehicle,
always use a tire that has the same
load rating as the factory installed
tire.
7. Uniform Tire Quality Grading
Quality grades can be found where
applicable on the tire sidewall
between tread shoulder and maxi -
mum section width.
For example:
Treadwear 200
Traction AA
Temperature A
Tires degrade over time, even when
they are not being used. Regardless
of the remaining tread, we recom -
mend that tires be replaced after
approximately six (6) years of nor -
mal service. Heat caused by hot cli -
mate or frequent high loading
conditions can accelerate the aging
process.
Tread wear
The tread wear grade is a compara -
tive rating based on the wear rate
of the tire when tested under con -
trolled conditions on a specified
government test course. For exam -
ple, a tire graded 150 would wear
one-and-a-half times (1 ) as well
on the government course as a tire
graded 100.
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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.
These grades are molded on the
side-walls of passenger vehicle
tires. The tires available as standard
or optional equipment on your vehi -
cle 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 tire's ability to
stop on wet pavement as measured
under controlled conditions on spec -
ified government test surfaces of
asphalt and concrete. A tire marked
C may have poor traction perfor -
mance.
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 char -
acteristics.
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 labora -
tory test wheel.
Sustained high temperature can
cause the material of the tire to
degenerate and reduce tire life, and
Tires and wheels
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