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Inflation -- Tire Pressure
The Certificationflire label, which is on the rear edge of
the driver’s door, shows the correct inflation pressures
for your tires when they’re cold.
“Cold” means your
vehicle has been sitting for at least three hours or driven
no more than
1 mile (1.6 km).
NOTICE:
Don’t let anyone tell you that underinflation or
overinflation is all right. It’s not. If your tires
don’t
hav.2 enough air (underinflation), you can
get the following:
Too much flexing
Too much heat
Tire overloading
0 Bad wear
Bad handling
Bad fuel economy.
NOTICE: (Continued)
NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
Check your tires once
a month or more. Also, check the
tire pressure
of the spare tire.
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How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on
the valve
stems. They help prevent leaks by keeping out dirt
and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
(10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires as soon as possible and check
wheel alignment. Also check for damaged tires or
wheels. See “When It’s Time for New Tires” and
“Wheel Replacement” later in this section for more
information. If your vehicle has dual rear wheels,
also see “Dual Tire Operation” later
in this section. The purpose
of regular rotation is to achieve more
uniform wear for all tires
on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services” in the Index for scheduled
rotation intervals.
If
your vehicle has single rear wheels, always use one of
the correct rotation patterns shown
here when rotating
your tires.
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your vehicle has dual rear wheels, always use one of
me correct rotation patterns shown here when rotating
your tires.
When
you install dual wheels, be sure the vent holes in
the inner and outer wheels on each side are lined up.
After the tires have been rotated, adjust the front
and rear inflation pressures as shown on the
Certificatioflire label. Make certain that all wheel
nuts are properly tightened. See “Wheel Nut Torque”
in the Index.
’ A CAUTION:
Rust or dirt on a wheel, or on the parts to which
it is fastened, can make wheel nuts become loose
after
a time. The wheel could come off and cause
an accident. When you change a wheel, remove
any rust
or dirt from places where the wheel
attaches to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this; but be
sure to use a scraper or wire brush later,
if you
need to, to get all the rust or dirt off. (See
“Changing a Flat Tire” in the Index.)
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When It’s Time for New Tires
One way to tell when it’s
time for new tires is
to
check the treadwear
indicators, which will
appear when your tires have
only 1/16 inch (1.6 mm) or
less of tread remaining.
Some commercial truck
tires may
not have
treadwear indicators.
You need a new tire if any of the following statements
are true:
0 You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut or snagged deep
enough to show cord or fabric.
0 The tire has a bump, bulge or split.
0 The tire has a puncture, cut or other damage that
can’t be repaired well because
of the size or location
of
the damage.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel
bolt or wheel
nut is replaced, check the wheel nut
torque after 100,
1,000 and 6,000 miles (160, 1 600 and
IO 000 km) of driving. For proper torque, see “Wheel
Nut Torque”
in the Index.
The outer tire
on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more
evenly and last longer if you rotate
the tires periodically.
If you’re going to be doing a lot of driving on
high-crown roads, you can reduce tire wear by adding
5 psi (35 kPa) to the tire pressure in the outer tires. Be
sure
to return to the recommended pressures when no
longer driving under those conditions. See “Changing a
Flat Tire”
in the Index for more information.
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’
A CAUTION:
If you operate your vehicle with a tire that is
badly underinflated, the tire can overheat. An
overheated tire can lose air suddenly or catch
fire. You or others could be injured. Be sure all
tires (including the spare) are properly inflated.
Buying New Tires
To find out what kind and size of tires you need, look at
the Certificationmire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number
on each tire’s sidewall. When you get new tires,
get ones with that same TPC Spec number. That way
your vehicle will continue to have tires that are designed
to give proper endurance, handling, speed rating,
traction, ride and other things during normal service
on your vehicle. If your tires have an all-season tread
design, the TPC number will be followed by an
“MS”
(for mud and snow). If
you ever
replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.
I
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.
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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 (straight ahead) traction tests and
does not include cornering (turning) traction.
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.
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Whenever a wheel, wheel bolt or wheel nut is replaced
on a dual wheel setup, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque, see “Wheel Nut Torque”
in the Index.
See “Changing
a Flat Tire” in the Index for more
information.
I 3 Wheels
A CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can’t know how it’s been used or
how far it’s been driven.
It could fail suddenly
and cause an accident. If you have to replace
a
wheel, use a new GM original equipment wheel.
Tire Chains
NOTICE:
Use tire chains only where legal and only when you
must. Use chains that are the proper size for your
tires. Install them on the tires
of the rear axle.
Tighten them as tightly
as possible with the ends
securely fastened. Drive slowly and follow the
chain manufacturer’s instructions.
If you can
hear the chains contacting your vehicle, stop
and retighten them.
If the contact continues,
slow down until it stops. Driving too fast
or
spinning the wheels with chains on will
damage your vehicle.
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I IMPORTANT: I
KEEP ENGINE OIL
AT THE PROPER
LEVEL AND CHANGE
AS
RECOMMENDED
Introduction
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. All recommended maintenance procedures
are important. Improper vehicle maintenance can even
affect the quality
of the air we breathe. Improper fluid
levels or
the wrong tire inflation can increase the level
of emissions from your vehicle. To help protect our
environment, and to keep your vehicle in good
condition, please maintain your vehicle properly.
Have you purchused the GM Protection Plan? The Plan
supplements
your new vehicle warranties. See your
Warranty and Owner Assistance booklet,
or your GM
dealer for detuils.
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