1998 PONTIAC GRAND PRIX Owners Manual

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 Pa).
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.
I I
I When rotating your tires, always use the correct rotation
pattern shown here.
Don’t include the compact spare tire
in your
tire rotation.
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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.
L
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.)
I I
When It’s Time for New Tires
.. I
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:
0
0
0
0
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.
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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.
A CAUTION:
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.
I A CAUTION:
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.
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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.
'haction -- 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.
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Temperature -- A, B, C
The temperature grades are A (the highest), B, and Cy
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
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-canying
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
Pontiac model.
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’
A CAUTION:
Used Replacement Wheels
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.
‘ 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:
If your vehicle has P225160R16 size tires, don’t
use tire chains. They can damage your vehicle
because there’s not enough clearance.
NOTICE: (Continued)

.~
NOTICE: (Continued)
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 front tires.
If you have other tires, 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.
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.
Never use these to clean your vehicle:
a Gasoline
0 Benzene
0 Naphtha
0 Carbon Tetrachloride
0 Acetone
0 Paint Thinner
0 Turpentine
0 Lacquer Thinner
Nail Polish Remover
They can all be hazardous
-- some more
than others -- and they can all damage your vehicle, too.
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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
Reducing Agents
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.
0 Carefully scrape off any excess stain.
0 Use a clean cloth or sponge, and change to a clean area
If a ring forms after spot cleaning, clean the entire
often. A soft brush may be used
if stains are stubborn.
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.
Special Fabric Cleaning Problems
Stains caused by such things as catsup, coffee (black),
egg, fruit, fruit juice, milk, soft
drinks, vomit, urine and
blood can be removed
as follows:
1. Carefully scrape off excess stain, then sponge the
soiled area with cool water.
2. If a stain remains, follow the multi-purpose interior
cleaner instructions described earlier.
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