Downloaded from www.Manualslib.com manuals search engine 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
0 Tire overloading
0 Bad wear
Bad handling
Bad fuel economy.
If your tires have too much air (overinflation),
you can get the following:
Unusual wear
Bad handling
0 Rough ride
0 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
( 10 000 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.
a
Downloaded from www.Manualslib.com manuals search engine 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 Maintenance Schedule
booklet 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.
I A CAUTION:
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.)
6-41
Downloaded from www.Manualslib.com manuals search engine When It’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 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.
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.
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 consiruction type (bias,
0 The tread or sidewall is cracked, cut or snagged deep bias-belted or radial) as your original tires.
enough to show cord or fabric.
6-42
Downloaded from www.Manualslib.com manuals search engine I 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.
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.
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.
6-43
Downloaded from www.Manualslib.com manuals search engine 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.
6-44
Downloaded from www.Manualslib.com manuals search engine Wheel Replacement
~eplace any wheel that is bent. cracked, or badly ruslea
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.
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
Cadillac model.
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.
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.
6-45
Downloaded from www.Manualslib.com manuals search engine Used Replacement Wheels Tire Chains
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.
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.
6-46
Downloaded from www.Manualslib.com manuals search engine Cleaning Aluminum or Chrome
Wheels
(If Equipped)
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 vehicle. Don’t use strong soaps,
chemicals, abrasive polishes, abrasive cleaners or
abrasive cleaning brushes on them because you could
damage the surface. You may use chrome polish on
chrome wheels, but avoid any painted surface of the
wheel, and buff off immediately after application.
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.
I NOTICE: I
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 cofrosion protection.
Finish Damage
Any stone chips, fractures or deep scratches in the finish
should be repaired right away. Bare metal will corrode
quickly and may develop into a major repair expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer
or other service
outlets. Larger areas
of finish damage can be corrected
in your dealer’s body and paint shop.