1997 PONTIAC FIREBIRD tires

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 1 mile ( 1.6 km).
If you’ll be driving at speeds higher than
100 mph
(160 kdh) 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.
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
0 Bad wear
0 Bad handling
0 B,ad fuel economy.
If your tires have too much air (overinflation),
you can get the following:
0 Unusual wear
0 Bad handling
Rough ride
0 Needless damage from road hazards.
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When to Check
Check your tires once a month or more.
uon’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.
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.
If you don’t have P245/5OZR16 or P275/40ZR17
Goodyear Eagle GS-C tires, use the rotation pattern
shown above for your tires.
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If you have P245/50ZRl6 or P27940ZR17 Goodyear
Eagle
GS-C 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.
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
Rust or dirt on a wheel, or on the pa; cJ to which
it is fastened, can make wheel nuts become loose
after a time.
The wheel could come off and caus’e
an accident.
When you change a wheel, remove
any rust or dirt frolm 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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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:
0 You can see the indicators at three or more places
around the tire.
0 You can see cord or fabric showing through the
tire’s rubber.
0 The tread or sidewall is cracked, cut or snagged deep
enough to show cord
or fabric.
0 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.

Mixing tires could cause you to lose control while
driving.
If you mix tires of dif€erent sizes or types
(radi,al
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 0n 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 lirnited-pro'duction 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 gov'esnrnent 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.
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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 (straightahead) 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.

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
Pontiac 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
CM
original equipment parts. This way, you will be sure to
have the right wheel, wheel. bolts and wheel nuts
for
your Pontiac 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.
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Used Replacement Wheels
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.
Tire Chains
NOTICE:
If your Pontiac has P235/55R16, P245/50ZR16 or
P275/40ZR17 size tires, don’t use tire chains.
They can damage your vehicle.
If you have other tires, 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 rear 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.
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