1993 OLDSMOBILE SILHOUETTE tires

Service & Appearance Care
248
Inflation-Tire Pressure
The CertificatiodTire 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 a
mile. 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:
Too much flexin1
Too much heat
Tire overloadine
Bad wear
Bad handling
Bad fuel economy.
If your tires have too much air
(overinflation), you can get:
Unusual wear
Bad handling
Rough ride
Needless damage from road
I
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. Simply looking at
the tires will not tell you the pressure,
especially if you have radial tires-
which may look properly inflated even if
they’re underinflated.
If your tires have valve caps, be sure to
put them back on. They help prevent
leaks by keeping out dirt and moisture.
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Tire lnspection and Rotation
ro make your tires last longer, have them
[nspected and rotated at the mileages
recommended in the Maintenance
Schedule. See the
Index under
Ycheduled Maintenance Services.
Use this rotation pattern. After the tires
nave been rotated, adjust the front and
rear inflation pressure
as shown on the
Zertification/Tire label. Make certain
:hat all wheel nuts are properly
ightened. See the
Index under Wheel
Vut Torque.
1
b the parts to which it i
astened, can make wheel
3ecome loose after a time.
wheel could come off and cause an
dccident. When you change a
wheel, remove any
rust or dirl
from places where the wheel
ttaches
to the vehicle. In ar
ergency, you can use a clot1
L paper towel to do this; but b
sure
to use a scraper or wire 1:
later, if you need to, to get all the '
rust or die off. (See the Idex
under Changing a Flat Tire).
When lt's 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
2/32 inch (1.6 mm) or
less
of tread remaining.
You need a new tire if:
You can see the indicators at three
You can see cord or fabric showing
The tread or sidewall is cracked, cut
places
around the tire,
through the tire's rubber.
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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Sewice & Appearance Care
250
Buying New Tires
To find out what kind and size of tires
you need, look at the Certification/Tire
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 a
“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. Be sure to use the same size
and type tires on all four wheels.
It’s all right
to drive with your
compact spare, though.
It was
developed for use on your vehicle.
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.)
u
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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%) 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. 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.
251
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Service & Appearance Care
252
Temperature-A, B, C (CONT)
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.
Those grades are molded on the
sidewalls of passenger car tires.
While the tires available as standard or
optional equipment on General Motors
vehicles may vary with respect to these
grades, all such tires meet General
Motors performance standards and have
been approved for use on General Motors vehicles.
All passenger type
(P Metric) tires must conform to Federal
safety requirements in addition to these
grades.
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.
In most cases, you will not need to have
your wheels aligned again. 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. If wheel nuts keep
coming loose, the wheel, wheel bolts,
and wheel nuts should be replaced. If
the wheel leaks air out, replace it
(except some aluminum wheels, which
can sometimes be repaired). See your
Oldsmobile 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.
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 you have the right wheel,
wheel bolts, and wheel nuts for your Oldsmobile model.
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Used Replacement Wheels Tire Chains
Using the wrong replacement
b 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
)r others could be injured. Always
lse the correct wheel, wheel bolts,
1 and wheel nuts for replacement.
IL
The wrong wheel can also cause
problems with bearing life, brake cooling, speedometer/odometer
calibration, headlight aim, bumper
height,
vehicle ground clearance,
adtire
or tire chain clearance to
.the-body
.~ and chassis,;f,;,ir, ~ ~~~ .. .~. ..~ = ~ ~=.=.=~~~~ ... ~~
Putting a used wheel on your
vehicle is dangerous. You
can t
know how it’s been used or
how many miles it’s been driven. It
-ould fail suddenly and cause an
,ccident. If
you have to replace a
wheel, use
a new GM original
equipment wheel.
e
Use tire chains only when y
must. Use only SAE Class ‘23’’
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 manu-
facturer’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 with chains on will damage your
vehicle.
:l I ’
I
. .. ..
253
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Service & Appearance Care
260
Aluminum Wheels
Don't use chrome polish on your
aluminum wheels. Use wax after you
clean them. Also, don't
use abrasive
cleaners or cleaning brushes on them-
you could damage the protective
coating.
?;<,wash that has hard silicon carbide
,+:cleaning
>+=; brushes. These brushes
&??&an-take
%.?-_ . . off the protective coating. I
',I. : - .. .
White Sidewall Tires
Your Oldsmobile dealer has a GM
White Sidewall Tire Cleaner. You can
use
a stiff brush with it.
Weatherstrips
These are places where glass or metal
meets rubber. Silicone grease there will
make them last longer, seal better, and
not squeak. Apply silicone grease with a
clean cloth at least every six months.
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Maintenance Schedule
Section A: Scheduled Maintenance Services (Cont.)
284
Explanation of Scheduled Maintenance Services
Below are explanations of the services listed in Schedule I
and Schedule II.
The proper fluids and lubricants to use are listed in
Section D. Make sure whoever services your vehicle uses
these. All parts should be replaced
and all necessary repairs
done before you or anyone else drives the vehicle.
ITEM
NO. SERVICE
1 Engine Oil and Filter Chang@-Always use SG
Energy Conserving
II oils of proper viscosity. The
“SG” designation may be shown alone or in
combination with others, such as “SG/CC,” “SG/CD,” or
“SF, SG, CC,” etc. To determine the
preferred viscosity for your vehicle’s engine (e.g.,
SAE 5W-30 or SAE 10W-30), see the
Index under
Engine Oil.
2 Chassis Lubrication-Lubricate the transaxle shift
linkage, parking brake cable guides, underbody
contact points and linkage. Lubricate the front
suspension and steering linkage. NOTE:
To determine your engine’s displacement and code,
see the
Index under Engine IdentiJication.
ITEM
NO. SERVICE
3 Throttle Body Mounting Bolt Torque (3.a
Code D engine only) *-Check the torque of the
mounting bolts and/or nuts.
4 Tire and Wheel Rotation and Inspection-For
proper wear and maximum tire life, rotate your
tires following the instructions
in this manual. See
the
Index under Eres, Inspection & Rotation.
Check the tires for uneven wear or damage. If you
see irregular or premature wear, check the wheel
alignment. Check for damaged wheels
also.
* An Emission Control Senice.
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