wheel Oldsmobile Aurora 1998 s Workshop Manual

I A CAUTION:
Things that burn can get on hot engine parts and
start a fire. These include liquids like gasoline,
oil, coolant, brake fluid, windshield washer and
other fluids, and plastic or rubber. You or others
could be burned. Be careful not to drop or spill
things that will burn onto a hot engine.
The following sections tell you how to check fluids,
lubricants and important parts underhood.
Hood Release
To open the hood, first pull
the hood release handle
inside the vehicle, located to
the left of the steering wheel
under the instrument panel. Then
go to the front
of the vehicle and pull up on the
underhood release.
Lift the hood.
Before closing the hood, be sure
all the filler caps are on
properly. Then pull the hood down and close it fiiy.
6-9

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 pushing on the brake
pedal firmly).
A CAUTION:
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.
I NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
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.”
Brake Pedal Travel
See your retailer 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 apply the brakes, with or without the
vehicle moving, your brakes adjust for wear.
6-30

When to Check
Check your tires once a month or more.
Don’t forget your compact spare tire. It should be at
60 psi (420 Wa).
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. When
rotating your tires, always use the correct
rotation pattern shown here.
Don’t include the compact spare tire in your
tire rotation.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown
on the Tire-Loading
Information label. Make certain that all wheel nuts
are properly tightened. See “Wheel Nut Torque” in
the Index.

When It’s Time for New Tires
-
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.)
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.
You need a new tire if any of the following statements
are true:
You can see the indicators at three or more places
You can see cord or fabric showing through the
around
the tire.
tire’s rubber.
e The tread or sidewall is cracked, cut or snagged deep
enough to show cord or fabric.
e The tire has a bump, bulge or split.
e The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or location
of the damage.
6-46

Buying New Tires
To find out what kind and size of tires you need, look at
the Tire-Loading Information 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. 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.
It’s all right to drive with your compact spare,
though. It was developed for use on your vehicle.
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.
6-47

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 (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.
6-48

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
retailer if any of these conditions exist.
lour retailer 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 Aurora model.
T' 'Y:
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.
See “Changing a Flat Tire” in the Index for more
information.
Used Replacement Wheels
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 only
SAE Class “S” type chains
that are the proper size for your tires. Install
them on the front tires and 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.
6-50

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 or Chrome 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 car. 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.
1 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.
6-56

Power Steering
Pump Only ....................... 1 pint (0.5 L)
Complete System ............... 1.5 pints (0.7 L)
Tire Pressures ...... See Tire-Loading Information
label on the rear edge
of the driver’s doox
Wheel Nut Torque .......... 100 lb-ft (140 Nam)
Refrigerant (R=134a),
Air Conditioning
.... See refrigeran.t charge label
under the hood.
NOTE: All capacities are approximate. When adding,
be sure to fill
to the appropriate level as recommended
in this manual.
Air Conditioning Refrigerants
Not all air conditioning refrigerants are the same.
If the air conditioning system
in your vehicle needs
refrigerant, be sure the proper refrigerant is used.
If
you’re not sure, ask your retailer.
Engine Specifications
VIN Engine Code ........................... C
Type
.................................... V8
Displacement ............................. 4 L
Horsepower ............................. 250
Compression Ratio
...................... 10.3: 1
Firing Order ................... 1-2-7-3-4-5-6-8
Thermostat Temperature
Specification
................... 180°F (82°C)
Normal Maintenance
Replacement Parts
Air Cleaner Element .......... AC Type A-1096C
Engine Oil Filter
................ AC Type PF-58
Gap:
0.050 inch (1.52 mm)
Spark Plugs
................... AC Type 4
1-929
Windshield Wiper Blades
Type
............................... 6.32Pin
Length
..................... 22 inches (56 cm)