1998 PONTIAC FIREBIRD Owners Manual

Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about
your tire wmanty and where to obtain service, see
your Pontiac Warranty booklet for details.
I A CAUTION:
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.
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.
CAUTION: (Continued) CAUTION:
(Continued)
I
Overinflated tires are mo
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.
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Inflation -- Tire Pressure
The Tire-Loading Information label, which is 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
I mile (1.6 km).
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 Wa), whichever is lower. See the example below.
When you end this high-speed driving, return to the cold inflation pressures 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.) 0 300 kPa (44 psi) Max. Press.
For this example, you would set the inflation pressure
for high-speed driving at
38 psi (265 Wa).
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:
0 Too much flexing
0 Too much heat
0 Tire overloading
0 Bad wear
0 Bad handling
Bad fuel economy.
If your tires have too much air (overinflation),
you can get the following:
Unusual wear
0 Bad handling
0 Rough ride
0 Needless damage from road hazards.
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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 Pa).
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.
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 Index for scheduled
rotation intervals.
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If you don’t have P245/50ZR16 Goodyear Eagle GS-C
tires or
P27Y4OZR17 Goodyear Eagle F1-GS tires, use
the rotation pattern shown above for
your tires.
1
c
LI
If you have P245/50ZR16 Goodyear Eagle GS-C tires
or P275/4OZR17 Goodyear Eagle F1-GS tires, they
must roll in a certain direction for the best overall
performance. The direction is shown by an arrow on
the sidewall. Because these tires are directional, they
should be rotated
as shown here. These tires should
only be moved from front to rear and rear to front on
the same side of the vehicle.
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 Tire-Loading
Information label. Make certain that
all wheel nuts
are properly tightened. See “Wheel Nut Torque” in
the Index.
1 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
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 tread or sidewall is cracked, cut or snagged deep
enough
to show cord or fabric.
The tire has a bump, bulge or split.
0 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 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.
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.
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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.
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.
%action -- 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.
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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.
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
Pontiac model.
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