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Maintenance
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 perform-
ance.
The traction grade assigned to this
tire is based on straight-ahead brak-
ing 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 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. Grades B and A
represent higher levels of perform-
ance on the laboratory test wheel
than the minimum required by law.
Tire terminology and definitions
Air Pressure: The amount of air
inside the tire pressing outward on
the tire. Air pressure is expressed in
pounds per square inch (psi) or kilo-
pascal (kPa).
Accessory Weight: This means the
combined weight of optional acces-
sories. Some examples of optional
accessories are, automatic
transaxle, power seats, and air con-
ditioning.
Aspect Ratio: The relationship of a
tire's height to its width.
Belt: A rubber coated layer of cords
that is located between the plies and
the tread. Cords may be made from
steel or other reinforcing materials.
Bead: The tire bead contains steel
wires wrapped by steel cords that
hold the tire onto the rim.
Bias Ply Tire: A pneumatic tire in
which the plies are laid at alternate
angles less than 90 degrees to the
centerline of the tread.
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