ESP GMC SIERRA 1997 Owner's Manual

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Mixing tires could cause you to lose control while
driving.
If you mix tires of different sizes or types
(radial and bias-belted tires), the vehicle may not
handle properly, and
you could have a crash.
Using tires
of different sizes may also cause
damage to your vehicle. Be sure to use the same
size and type tires on all wheels.
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
Performance Criteria (TPC) 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
( 1 1/2) times as well on the government course as a tire
graded
100. 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.
Traction -- A, B, C
The traction grades, from highest to lowest, are A, B, and
C, and they represent the tire’s ability to stop on wet
pavement as measured under controlled conditions on
specified government test surfaces
of asphalt and concrete.
A tire marked C may have poor traction performance.
Warning: The traction grade assigned to this tire is based
on braking (straightahead) 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 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. 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
GM 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.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only
with new GM original
equipment parts. This way, you
will be sure to have the
right wheel, wheel bolts
and wheel nuts for your vehicle.
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Roadside Assistance
1
GMC’s Roadside Assistance provides stranded owners
with over-the-phone roadside repairs, location of the
nearest
GMC dealer or the following special services:
FZat Tire Change: Installation of spare tire will be
covered at no charge (customer is responsible for repair
or replacement of tire).
Fuel Delivery: Delivery of enough fuel for the customer
to get to the nearest service station (up to
$4.00) will
be covered.
Jump Start: No-start situations which require a battery
jump start will be covered at no charge.
Lock Out: Replacement keys or locksmith service will
be covered at no charge if you are unable to gain entry
into your vehicle. Delivery of
the replacement key will
be covered at no charge within
10 miles (16 km).
Emergency Towing Service: Towing to the nearest
GMC dealer for warranty related disablements will
be covered.
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