1998 GMC SIERRA Owners Manual

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.)
1 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.
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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.
The tire has a bump, bulge or split.
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
10 000 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.
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,
if any) are properly inflated.
Buying New Tires
To find out what kind and size of tires you need, look at
the CertificatiodTire label.
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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.
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.
I A CAUTION:
If you use biasuply tires on your vehicle, the
wheel rim flanges could develop cracks after
many miles of driving.
A tire and/or wheel could
fail suddenly, causing a crash. Use only radial-ply
tires with the wheels on your vehicle.
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
I 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 I2 inches (25 to 30 cm),
or to some limited-production tires.
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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 (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.
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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 corning 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
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.
~ Using the wrong replacement wheels, wheel bolts
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use
the correct wheel, wheel bolts and wheel nuts
for replacement.
~
NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, 'bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
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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.
Used Replacement Wheels
/!1 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:
If your vehicle has dual wheels, P265/75R16 or
LT265/75R16 size tires, don’t use tire chains.
They can damage your vehicle because there’s
not enough clearance.
Use another type of traction device only
if its
manufacturer recommends it for
use on your
vehicle and tire size combination and road
conditions.
Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device
if it’s contacting your vehicle, and don’t
spin your wheels.
If you do find traction devices that will fit, install
them on the rear tires.
NOTICE: (Continued)
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NOTICE: (Continued) -
If you don’t have dual wheels or if you have a tire
size other than
P265/75R16 or LT265/75R16, 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.
Don’t use chains on the tires of the front 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.
Appearance Care
Remember, cleaning products can be hazardous. Some
are toxic. Others can burst into flame
if you strike a
match or get them on
a hot part of the vehicle. Some are
dangerous if
you breathe their fumes in a closed space.
When you use anything from
a container to clean your
vehicle, be sure
to follow the manufacturer’s warnings
and instructions. And always open your doors or
windows when you’re cleaning the inside.
NevcJr use these to clean your vehicle:
0 Gasoline
Benzene
Naphtha
0 Carbon Tetrachloride
0 Acetone
0 Paint Thinner
Turpentine
0 Lacquer Thinner
0 Nail Polish Remover
They can
all be hazardous -- some more th .an others --
and they can all damage your vehicle, too.
Don’t use any
of these unless this manual says you can.
In many uses, these will damage your vehicle:
Alcohol
Laundry Soap
0 Bleach
0 Reducing Agents
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Cleaning the Inside of Your Vehicle
Use a vacuum cleaner often to get rid of dust and loose
dirt. Wipe
vinyl, leather, plastic and painted surfaces
with a clean, damp cloth.
Your dealer has two cleaners, Multi-Purpose Interior
Cleaner and Capture Non-Solvent Dry Spot and Soil
Remover for cleaning fabric and carpet. They
will
clean normal spots and stains very well. You can get
GM-approved cleaning products from your dealer. (See
“Appearance Care and Materials‘‘
in the Index.)
Here are some cleaning tips:
Always read the instructions on the cleaner label.
Clean up stains as soon
as you can -- before they set.
Carefully scrape
off any excess stain.
Use a clean cloth or sponge, and change to a
clean area often.
A soft brush may be used if
stains are stubborn.
If a ring forms after spot cleaning, clean the entire
area immediately
or it will set.
Using Multi-Purpose Interior Cleaner
on Fabric
1.
2.
3.
4.
5.
6.
7.
Vacuum and brush the area to remove any loose dirt.
Always clean a whole trim panel or section.
Mask
surrounding trim along stitch or welt lines.
Mix powdered cleaner following the directions on
the container label to form thick suds.
Use suds only and apply with a clean sponge. Don’t
saturate the material and don’t rub
it roughly.
As soon as you’ve cleaned the section, use a sponge
to remove the suds.
Wipe cleaned area with
a clean, damp towel or cloth.
Wipe with a clean cloth and let dry.
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