1998 Oldsmobile Achieva Owner's Manuals

CAUTION: (Continued)
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Overloading your tires can cause
overheating as a result of too much friction.
You could have an air-out and
a serious
accident. See “Loading Your Vehicle” in
the Index.
Underinflated tires pose the same danger
as
overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinflated tires are more likely to be
cut, punctured or broken by
a sudden
impact
-- such as when you hit a pothole.
Keep tires at the recommended pressure.
Worn, old tires can cause accidents.
If your
tread is badly worn, or if your tires have
been damaged, replace them.
Inflation -- Tire Pressure
The Tire-Loading Information 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 have enough air (underinflation), you can
get the following:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
0 Bad fuel economy.
NOTICE: (Continued)
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NOTICE: (Continued)
If your tires have too much air (overinflation),
you
can get the following:
Unusual wear
0 Bad handling
Rough ride
Needless damage from road hazards.
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 OOO to 13 O00 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.
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When It’s Time for New Tires 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.
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
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
0 The tread or sidewall is cracked, cut or snagged
The tire has a bump, bulge or split.
0 The tire has a puncture, cut or other damage that
deep
enough to show cord or fabric.
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.
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.
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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.
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.
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.
Your 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
Oldsmobile model.
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I A CAUTION:
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.
I 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. 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
I NOTICE:
If your vehicle has P195/65R15 size tires, don’t
use tire chains. They can damage your vehicle
because there’s not enough clearance.
NOTICE: (Continued)
See “Changing a Flat Tire” in the Index for
mare information.
6-43

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:
Gasoline
0 Benzene
Naphtha
0 Carbon Tetrachloride
0 Acetone
Paint Thinner
Turpentine
Lacquer Thinner
0 Nail Polish Remover
They can all be hazardous
-- some more than
others
-- and they can all damage your vehicle, too.
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