1998 CADILLAC DEVILLE tires

Downloaded from www.Manualslib.com manuals search engine 0 There should not be any cargo or loading of the
vehicle, except it should have a full tank of gas and
one person or 160 lbs. (75 kg) on the driver’s seat.
Tires should be properly inflated.
0 Rock the vehicle to stabilize the suspension.
NOTICE:
L
To make sure your headlamps are aimed
properly, read all the instructions before
beginning. Failure to follow these instructions could cause damage to headlamp parts.
For the vertical adjustment, state inspection stations
generally will allow a reading of plus 0.76 degrees or
minus 0.76 degrees from the center of the bubble.
It is recommended that the upper limit not exceed plus
0.4 degrees from the center of the bubble. Other drivers
may flash their high beams at you if your adjustment
is
much above plus 0.4 degrees. If you
find that the headlamp aiming needs adjustment,
follow these steps:
..
. ,..
1. Start by opening the hood and locating the vertical
and horizontal aim indicators. The aiming screw for
the horizontal aim indicator is on the outboard side
of the headlamp cover and the aiming screw for the
vertical aim indicator is on the inboard side.
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Downloaded from www.Manualslib.com manuals search engine Tires
Your ~ew 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-Cadillac Warranty booklet for details.
I-
A CAUTION:
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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.
‘0 Underinflated tires pose the same danger as
overloaded tires. The resultihg accident
could cause serious injury. Check all tires
frequently to maintain the recommended’
pressure. Tire pressure should be checked when
your tires are cold.
CAUTION: (Continued) CAUTION:
(Continued)
0 Overinflated tires are more likely to be
cut, punctured or broken by
a sudden
impact
-- such las when you hit a pothole.
Keep tires at the recommended pressure.
0 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.
Inflation -- Tire Pressure
The Tire-Loading Information label, which is located on
the rear edge of the driver’s door, shows the correct
inflatiop 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).
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If you’ll be driving at high speeds (e.g., speeds of 100 mph
(160 km/h) or higher), where it is legal, set the cold
inflation pressure to the maximum inflation pressure shown on the
tire sidewall, or to 38 psi (265 kpa),
whichever is lower. See the example below. When you end
this high-speed driving, return to the cold inflation
pressure shown on the Tire-Loading Information label.
Example:
You’ll find maximum load and inflation pressure molded
on the tire’s sidewall, in small letters, near the
rim flange. It will read something like this: Maximum load 690
kg (1521 lbs.) @ 300 Wa (44 psi) Max. Press.
For this example,
you would set the inflation pressure
for high-speed driving at
39 psi (265 kPa).
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
0 Too much heat
0 Tire overloading
NOTICE: (Continued)
NOTICE: (Continued)
Bad wear
Bad handling
0 Bad fuel economy.
If your tires have too much air (overinflation),
you can get the following:
0 Unusual wear
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.
They help prevent leaks
by keeping out dirt and moisture.
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Downloaded from www.Manualslib.com manuals search engine Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 rriiles
(10 000 to 13 000 krn). 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 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 Torqoe” 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.)
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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
You can see cord or fabric showing through the
The tread or sidewall is cracked, cut or snaggea
around the tire.
tire’s rubber. 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.
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.
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Downloaded from www.Manualslib.com manuals search engine '
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.
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
("PC) standards.
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Downloaded from www.Manualslib.com manuals search engine ~ ~~~~~~ ~ ____ ~~ ~~ ~~
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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 1/2) times as' well on the governmefit 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, B, 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
1 conditions on specified government test surfaces of
asphalt and concrete.
A tire marked C may have poor
I traction performance.
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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.
1 Warning: The traction grade assigned to this tire is based
on braking (straight ahead) traction tests and does not
include acceleration, cornering, hydroplaning, 'or peak
traction characteristics.
Temperature -- A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire's resistance to the generation of
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Downloaded from www.Manualslib.com manuals search engine 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.
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.
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.