tires OLDSMOBILE SILHOUETTE 2003 Owner's Manual

Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts
in
the proper sequence to GM torque specifications.
Your rear drum brakes don’t have wear indicators, but
if
you ever hear a rear brake rubbing noise, have the
rear brake linings inspected immediately.
Also, the rear
brake drums should be removed and inspected each
time the tires are removed for rotation or changing.
When you have the front brake pads replaced, have the
rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
See
Brake System Inspection on page 6-15.
Brake Pedal 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 apply the brakes, with or without the
vehicle moving, your brakes adjust for wear.
Replacing Brake System Parts
The braking system on a 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
need 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.
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Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer.
If you ever have questions
about your tire warranty and where to obtain service,
see your Oldsmobile Warranty booklet for details.
Poorly maintained and improperly used tires
are dangerous.
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.
CAUTION: (Continued]
0 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.
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Inflation - Tire Pressure
The Certificationflire label, which is on the rear edge ot
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
Bad fuel economy If your tires have too much air (overinflation),
you can get the following:
Unusual wear
e 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 kPa).
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.
moisture.
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Tire Inspection and Rotation
Tires should be rotated every 7,500 miles (12 500 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 Is Time
for New Tires on page
5-63 and Wheel Replacement
on page
5-66 for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire,
If it moves, use the
folding wrench to tighten the cable. See
Changing a Flat
Tire on page
5-70.
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 “Part A: Scheduled
Maintenance Services,” in Section
6, for scheduled
rotation intervals.
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 Certification/Tire
label. Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and
Specifications on page 5-
103.
-3ust 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.
When It Is 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.
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
The tread or sidewall is cracked, cut or snagged
The tire has a bump, bulge or split.
The tire has a puncture, cut or other damage that
around the tire.
tire’s rubber. 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 Certificationflire label.
The tires installed on your vehicle when it was new had a
Tire Petformance 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 coul-.
Lause 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 temporarily,
it was developed
for use on your vehicle. See “Compact Spare
Tire”
in the index.
If you use bias-ply
1 1s 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.
5-64

Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
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
Performance Criteria (TPC) standards.
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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
5) 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 - AA, A, 9, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades 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 straight-ahead braking
traction tests, and does not include acceleration,
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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 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.
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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
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.
See
Changing a Flat Tire on page 5-70 for more
information.
Used Replacement WI els
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 a crash. 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
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.
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5-67

Accessory Inflator
Your vehicle may have an air inflator. With it, you can
inflate things like air mattresses and basketballs,
and you can also use it to bring your tires up to the
proper pressure.
The air inflator is located in the rear compartment on
the driver’s side. To remove the cover, pull the tab
on the cover and pull it
off.
This is the switch for
the air inflator.
There may be an air inflator kit stored in the glove box.
It includes a 20-foot
(6 m) hose with an air pressure
gage and nozzle adapters.
....___ ting something too much can make it
explode, and you or others could be injured.
Be sure to read the inflator instructions, and
inflate any object only
to its recommended
pressure.
To use your air inflator system, do the following:
1. Turn the ignition to ACCESSORY or RUN.
2. Attach the appropriate nozzle adapter, if required,
to the end
of the hose that has the pressure gage.
3. Attach that end of the hose to the object you wish
to inflate.
4. Remove the protective cap covering the outlet.
5. Attach the other end of the hose to the outlet.
6. Press the accessory inflator switch. The light in the
switch will come on to show the system is working.
If the air inflator system does not turn on or the
light does not come on, the fuse may be blown or
installed incorrectly. See
Fuses and Circuit Breakers on
page 5-96 or see your dealer for service.
5-68