Saturn 2009 ASTRA - Manual (Page 242)

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
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.
The 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. It should be
noted that 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
buildup and possible tire failure.
{ WARNING
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 buildup and
possible tire failure.
Wheel Alignment and
Tire Balance
The tires and wheels on your
vehicle were aligned and balanced
carefully at the factory to give
you the longest tire life and best
overall performance. Adjustments to
wheel alignment and tire balancing
will not be necessary on a regular
basis. However, if you notice
unusual tire wear or your vehicle
pulling to one side or the other, the
alignment might need to be
checked. If you notice your vehicle
vibrating when driving on a
smooth road, the tires and wheels
might need to be rebalanced.
See your dealer/retailer for proper
diagnosis.
9-58 Vehicle Service and Care