ESP Oldsmobile Cutlass 1998 s User Guide

Uniform Tire Quality Grading
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance.
(This
applies only to vehicles sold in the United States.) The
grades are molded on the sidewalls of most passenger
car tires. The Uniform Tire Quality Grading system does
not apply to deep tread, winter-type snow tires,
space-saver or temporary use spare tires, tires with
nominal rim diameters of
10 to 12 inches (25 to 30 cm),
or to some limited-production tires.
While the tires available on General Motors passenger cars and light trucks may vary with respect to these
grades, they must also conform to Federal safety
requirements and additional General Motors Tire
Pedomance Criteria (PC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course. For
example, a tire graded 150 would wear one and a half
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(1 1/2) times as well on the government course as a tire ~
graded 100. The relative performance of tires depends 1
upon the actual conditions of their use, however, and
may depart significantly from the nom due to variations
in driving habits, service practices and differences in
road characteristics and climate. ! i
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Traction -- A, B, C
The traction grades, fkom highest to lowest, are A, B, and
C, and they represent the tire’s ability to stop on wet
pavement
as measured mder controlled conditions on
specified government test surfaces of asphalt and concrete.
A tire marked C may have poor traction perfomce.
Warning: The traction grade assigned to this tire is based
on braking (straight ahead) traction tests and does not
include cornering (turning) traction.

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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.
Wheel Alig1:::::Bt 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.
Scheduled wheel alignment and wheel balancing are not
needed. 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
retailer
if any of these conditions exist.
Your retailer will know the kind of wheel you need.
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