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.
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.
These grades
are molded on the sidewalls of passenger
car tires.
While
the tires available as standard or optional
equipment on General Motors vehicles
may vary with
respect to these grades, all such tires meet General
Motors performance standards and have been approved
for use on General Motors vehicles. All passenger type
(P Metric) tires must conform to Federal safety
requirements in addition to these grades.
Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at
the factory to give you the longest tire life
and best overall performance.
In most cases, you will not need to have your wheels
aligned again. However, if
you notice unusual tire wear
or your vehicle pulling one way or the other, the
alignment may need to be reset. If you notice your
vehicle vibrating when driving on a smooth road, your
wheels may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded.
If wheel nuts keep coming loose, the wheel,
wheel bolts, and wheel nuts should be replaced.
If the
wheel leaks air, replace it (except some aluminum
wheels, which can sometimes be repaired). See
your
Pontiac dealer if any of these conditions exist.
Your dealer will know the kind
of wheel you need.
Each new wheel should have the same load carrying
capacity, diameter, width, offset, and be mounted the
same way
as the one it replaces.
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ProCarManuals.com
