tires PONTIAC FIREBIRD 1999 Owner's Manual

yellowblue
6-46
Tires
Your new 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 Pontiac Warranty booklet for details.
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 ªLoading Your Vehicleº in
the Index.
CAUTION: (Continued)
CAUTION: (Continued)

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.

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 ªInflation -- Tire Pressureº in this section for
inflation pressure adjustment for higher
speed driving.

yellowblue
6-47 Inflation -- Tire Pressure
The Tire-Loading Information label, which is on the
rear edge of the driver's door, shows the correct
inflation pressures for your tires when they're cold.
ªColdº 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 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 kPa (44 psi) Max. Press.
For this example, you would set the inflation pressure
for high
-speed driving at 38 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

Too much heat

Tire overloading

Bad wear

Bad handling

Bad fuel economy.
If your tires have too much air (overinflation),
you can get the following:

Unusual wear

Bad handling

Rough ride

Needless damage from road hazards.

yellowblue
6-48
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.
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 ªWhen It's Time for New Tiresº and
ªWheel Replacementº 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 ªScheduled
Maintenance Servicesº in the Index for scheduled
rotation intervals.
If you don't have P245/50ZR16 Goodyear Eagle GS-C
tires or P275/40ZR17 Goodyear Eagle F1
-GS tires, use
the rotation pattern shown above for your tires.

yellowblue
6-49
If you have P245/50ZR16 Goodyear Eagle GS-C tires
or P275/40ZR17 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.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 wheelnuts are
properly tightened. See ªWheel Nut Torqueº in
the Index.
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
ªChanging a Flat Tireº in the Index.)

yellowblue
6-50
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.

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 ªMSº
(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.

yellowblue
6-51
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.
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.

yellowblue
6-52
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
-- 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
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 straight
-ahead braking
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
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.

yellowblue
6-53 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 vehicle.
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 ªChanging a Flat Tireº in the Index for
more information.

yellowblue
6-54
Used Replacement Wheels
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.
Tire Chains
NOTICE:
If your vehicle has P235/55R16, P245/50ZR16 or
P275/40ZR17 size tires, don't use tire chains.
They can damage your vehicle because there's
not enough clearance.
NOTICE: (Continued)
NOTICE: (Continued)
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer's
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it's contacting your vehicle, and don't
spin your wheels.
If you do find traction devices that will fit, install
them on the rear tires.
If you have other tires, use tire chains only where
legal and only when you must. Use only SAE Class
ªSº 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.

yellowblue
6-61
Cleaning Aluminum or
Chrome
-Plated 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, cleaners
with acid or abrasive cleaning brushes on them because
you could damage the surface. Do not use chrome polish
on any wheels other than chrome
-plated wheels.
Use chrome polish only on chrome
-plated 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.
NOTICE:
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 and tires.
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 corrosion protection.