wheel GMC ENVOY 1998 Repair Manual

NOTICE:
0 Using the wrong fluid can badly damage
brake system parts. For example, just
a few
drops of mineral-based oil, such as engine
oil, in your brake system can damage brake
system parts
so badly that they’ll have to be
replaced. Don’t let someone put in the
wrong kind of fluid.
If you spill brake fluid on your vehicle’s
painted surfaces, the paint finish can be
damaged. Be careful not to spill brake fluid
on your vehicle.
If you do, wash it off
immediately. See “Appearance Care” in
the Index.
Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that
make a high-pitched warning sound when the brake
pads are worn and new pads are needed. The sound
may come and
go or be heard all the time your vehicle
is moving (except when you are pushim on the brake
pedal firmly).
A CAU‘
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
NOTICE:
Continuing to drive with worn-out brake pads
could result
in costly brake repair.
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Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque
wheel nuts in the
proper sequence to
GM specifications.
Brake linings should always be replaced as complete
axle sets.
See “Brake System Inspection” in Section
7 of this manual
under Part
C “Periodic Maintenance Inspections.”
Brakc Jedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
Replacing Brake System Parts
The braking system on a modern vehicle is complex.
Its many parts have to be
of top quality and work well
together
if the vehicle is to have really good braking.
Your vehicle was designed and tested with top-quality
GM brake parts. When you replace parts of your braking
system
-- for example, when your brake linings wear
down and
you have to have new ones put in -- be sure
you get new approved GM replacement parts.
If you
don’t, your brakes may
no longer work properly. For
example,
if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change
-- for the worse. The braking
performance you’ve come to expect can change in many
other ways if someone puts
in the wrong replacement
brake parts.
Battery
Every new vehicle has an ACDelco Freedom@ battery.
You never have to add water to one of these. When it’s
time for a new battery, we recommend an ACDelco
Freedom battery. Get one that has the replacement
number shown on the original battery’s label.
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NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
0 Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
When to Check
Check your tires once a month or more. Also, check the
tire pressure
of the spare tire.
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.
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.
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Q
+
I
!
When rotating your tires, always use one of the correct
rotation. patterns shown here.
After the tires
have been rotated, adjust the front and rear
inflation pressures as shown on the Certificationflire
label.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque”
in the Index.
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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I Uniform Tire Quality Grading
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.
If you use bias-ply 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.
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.
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Treadwear Temperature -- A, B, C
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. 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
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
GMC model.
Replace any wheel that is bent, cracked, or badly rusted
Or wheel nuts on Your vehicle can be dangerous- or corroded. If wheel nuts keep coming loose, the wheel,
Using the wrong replacement wheels, wheel bolts
It could affect the braking and handling of your
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.
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.
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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
clearance to the body and chassis.
See “Changing a Flat Tire” in the Index for
more information.
Used Replacement Wheels
I
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:
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.
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Foreign materials such as calcium chloride and other
salts, ice melting agents, road oil and tar, tree sap, bird
droppings, chemicals from industrial chimneys, etc., can
damage your vehicle’s finish if they remain on painted
surfaces. Wash the vehicle
as soon as possible. If
necessary, use non-abrasive cleaners that are marked
safe for painted surfaces to remove foreign matter.
Exterior painted surfaces are subject to aging, weather
and chemical fallout that can take their toll over
a period
of years. You can help to keep the paint finish looking
new by keeping your vehicle garaged or covered
whenever possible.
Cleaning Aluminum Wheels
Keep your wheels clean using a soft clean cloth with
mild soap and water. Rinse with clean water. After
rinsing thoroughly, dry with a soft clean towel. A wax
may then be applied.
The surface
of these wheels is similar to the painted
surface of your vehicle. Don’t use strong soaps,
chemicals, abrasive polishes, abrasive cleaners or
abrasive cleaning brushes on them because you could
damage the surface. Don‘t take your vehicle through
an automatic car wash
that has silicon carbide tire cleaning brushes. These
brushes can
also damage the surface of these wheels.
Cleaning Tires
To clean your tires, use a stiff brush with a tire cleaner.
NOTICE:
When applying a tire dressing always take care
to wipe off any overspray or splash from all
painted surfaces on the body
or wheels of the
vehicle. Petroleum-based products may damage
the paint finish.
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair shop
applies anti-corrosion material
to the parts repaired or
replaced to restore corrosion protection.
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Appearance Care Materials Chart
PART NUMBER USAGE DESCRIPTION SIZE
994954 Exterior polishing cloth
Polishing Cloth - Wax
Treated
23 in. x 25 in.
1050172
Cleans
and lightly waxes Wash
Wax Concentrate
16 oz. (0.473 L) 1052870 Removes dirt,
grime, smoke
and fingerprints
Glass Cleaner
23 oz. (0.680 L) 1050427 Cleans
vinyl tops, upholstery and convertible tops
Vinyl
Cleaner
32
oz. (0.946 L) 1050214 Removes
soil and black marks from whitewalls
White Sidewall Tire Cleaner
16
oz. (0.473 L) 1050174 Use on chrome, stainless steel, nickel, copper and brass
Chrome
Cleaner and Polish
16 oz. (0.473 L) 1050173 Removes
tar, road
oil and asphalt
Tar and Road Oil Remover
16 oz. (0.473 L)
- ~~
1052918** Armor All TM Protectant 8 oz. (0.237 L) Protects leather, wood, acrylics, Plexiglas TM, plastic,
rubber and
vinyl
1052925
Attracts, absorbs and removes
soils Capture Dry Spot Remover 8 oz. (0.237 L) 1052930 Spray
on and rinse
with water
Wheel Cleaner
16 oz. (0.473 L) 1052929 16
oz. (0.473 L) Multi-Purpose
Interior
Cleans carpets, seats, interior trim, door panels
Cleaner and floor mats
12345002
16 oz. (0.473 L)
See your General Motors Parts Department for these products. **Not recommended for use on instrument panel vinyl.
Removes contaminants, blemishes and swirl marks
Surface Cleaner
16 oz. (0.473 L) 12377984 Removes light scratches and oxidation and protects finish
Cleaner
Wax 16
oz. (0.473 L) 12377966 Removes dust, fingerprints
and surface contaminants
Finish Enhancer
16
oz. (0.473 L) 12377964 Spray
on tire shine
Silicone Tire Shine
12
oz. (0.354 L) 12345725 Shines vehicle
without scratching
Synthetic Chamois
2.5
sq. ft.
1234572 1
Cleans and shines a variety of surface types
Armor All Cleaner
See “Fluids and Lubricants” in the Index.
--
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