1993 CADILLAC SEVILLE Owners Manual

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A CAUTION
Poorly maintained and improperly used tires are dangerous.
Overloading your tires can cause overheating as a result of
too much fkiction. 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 iqjury.
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.
See “Inflation
- Tire Pressure” in this section for inflation
pressure adjustment
for higher speed driving.
In@tion - Tire Pressure
The Tire-Loading Information label which is located on 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.
If you’ll be driving at speeds higher than
100 mph (160 kmh) where it is
legal, raise the “cold” inflation pressure
of each tire to 35 psi (240 kPa).
When you end this
very high speed driving, reduce the “cold” inflation
pressures
to those listed on the Tire-Loading Information label. Never
inflate the tires higher than the maximum “cold” inflation pressures
stated on the sidewall
of the tires.
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Downloaded from www.Manualslib.com manuals search engine When to Check Check your tires once a month or more.
The Seville tire pressures are:
Front - 28 psi (200 kPa)
Rear - 26 psi (179 kPa)
Seville recommended
tire size is:
XGT4 IIburing Design Blackwall (P225/6OR16)
The
STS tire pressures are:
Front - 29 psi (200 kPa)
Rear - 29 psi (200 kPa)
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Downloaded from www.Manualslib.com manuals search engine STS recommended tire size is:
GA Performance Blackwall (P225/60ZR 16)
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.
Tire Inspection and Rotation
To make your tires last longer, have them inspected and rotated at the
mileages recommended
in the Maintenance Schedule. See “Scheduled
Maintenance Services”
in the Index.
FRONT Use this rotation
pattern.
After the tires have been rotated, adjust the front and rear inflation
pressure as
shown on the Tire-Loading Information label. Make certain
that
all wheel nuts are properly tightened. See “Wheel Nut Torque’’ in the
Index.
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Downloaded from www.Manualslib.com manuals search engine 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.)
When It3 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
0 You can see the indicators at three 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 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.
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. 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.)
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Downloaded from www.Manualslib.com manuals search engine Deadwear
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. 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.
Those grades are molded on the sidewalls of passenger car tires.
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Downloaded from www.Manualslib.com manuals search engine 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.
meel 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 Cadillac 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 Ca\
dillac 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.
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Downloaded from www.Manualslib.com manuals search engine ~ ~ ~~~~ Used Replacement Wheels
A
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 dri\
ven.
It
could fail suddenly and cause an accident. If you have to replace
a wheel use
a ge~ GM original equipment wheel.
Tire Chains
’ NOTICE:
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