PONTIAC GRAND PRIX 2008 Owners Manual

Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specied
government test course. For example, a tire
graded 150 would wear one and a half (1.5) 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 signicantly 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 specied 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
specied 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 inated
and not overloaded. Excessive speed,
underination, or excessive loading, either
separately or in combination, can cause heat
buildup and possible tire failure.
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Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned
and balanced carefully at the factory to give you the
longest tire life and best overall performance.
Adjustments to wheel alignment and tire balancing will
not be necessary on a regular basis. However, if you
notice unusual tire wear or your vehicle pulling to one
side or the other, the alignment might need to be
checked. If you notice your vehicle vibrating when driving
on a smooth road, the tires and wheels might need to be
rebalanced. See your dealer/retailer for proper diagnosis.
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/retailer if any of these conditions exist.
Your dealer/retailer 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,
wheel nuts, or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts, wheel nuts, and TPMS sensors
for your vehicle.
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{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.
SeeChanging a Flat Tire on page 5-96for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
5-83

Tire Chains
{CAUTION:
If your vehicle has P225/55R17, P255/45R18 or
P225/50R18 size tires, do not use tire chains,
there is not enough clearance.
Tire chains used on a vehicle without the
proper amount of clearance can cause damage
to the brakes, suspension or other vehicle
parts. The area damaged by the tire chains
could cause you to lose control of your vehicle
and you or others may be injured in a crash.
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.
CAUTION: (Continued)
CAUTION: (Continued)
To help avoid damage to your vehicle, drive
slowly, readjust or remove the device if it is
contacting your vehicle, and do not spin your
wheels.
If you do nd traction devices that will t,
install them on the front tires.
Notice:If your vehicle does not have P225/55R17,
P255/45R18 or P225/50R18 size 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 front 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.
5-84

If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your tires properly. SeeTires
on page 5-62. If air goes out of a tire, it is much more
likely to leak out slowly. But if you should ever have a
blowout, here are a few tips about what to expect and
what to do:
If a front tire fails, the at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use in a
skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road if possible.If a tire goes at, and your vehicle has a spare tire, see
Changing a Flat Tire on page 5-96. This information
shows you how to use your vehicle’s tire changing
equipment and how to change a at tire safely.
{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a at tire.
5-85

If a Tire Goes Flat (GXP)
GXP models have no spare tire, no tire changing
equipment, and no place for storing a spare or at tire.
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place and stopping.
Then do this:
1. Turn on the hazard warning ashers. SeeHazard
Warning Flashers on page 3-6.
2. Park your vehicle. Set the parking brake rmly and
put the shift lever in PARK (P). SeeShifting Into
PARK (P) on page 2-34for additional information.
3. Turn off the engine.
4. Inspect the at tire.
If the tire has been separated from the wheel or has
damaged sidewalls or large tears that allow rapid air
loss, call a tire repair facility. SeeRoadside Assistance
Program on page 7-6.
If the at tire is due to a slow leak caused by a nail or
other similar road hazard, the tire inator kit may be
used to temporarily repair the damaged tire. The kit uses
a liquid tire sealant to seal small punctures in the tread
area of the tire. The at tire is then inated to at least
30 psi (207 kPa) and driven to evenly distribute the tire
sealant. The tire pressure is checked after driving for a
maximum of ve miles (8.0 km) to see if the slow leak has
been stopped. If the tire pressure is 19 psi (131 kPa) or
more, inate the tire up to the standard operatingpressure as shown on the tire and loading information
label. This label is attached to the vehicle’s center-pillar
below the driver’s door latch. SeeInflation - Tire Pressure
on page 5-69.
Notice:If the tire pressure has dropped below
19 psi (131 kPa), the vehicle should not be driven.
Damage to the tire may be severe and the sealant
will not be effective. Contact Roadside Assistance,
seeRoadside Assistance Program on page 7-6.
You should have the damaged tire repaired as soon as
possible. The tire sealant is a temporary repair only.
If the tire has been lled with tire sealant, take the tire to
a GM dealer/retailer for inspection and repair. See
Tire Sealant and Compressor Kit (GXP) on page 5-86
for additional information.
Tire Sealant and Compressor
Kit (GXP)
Your vehicle may have a tire inator kit. The kit uses a
liquid tire sealant and air at the same time to seal small
punctures in the tread area of the tire. Be sure to read
and follow all the tire inator kit instructions.
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The kit includes:
A. Air Compressor
B. Tire Sealant Canister
C. Air Compressor
Accessory Plug
D. On/Off SwitchE. Air Pressure Gage
F. Air Compressor
Inator Hose
G. Sealant Filling HoseIf the at tire is due to a slow leak caused by a nail or
other similar road hazard, the tire inator kit may
be used to temporarily repair the damaged tire.
After temporarily repairing a tire using the tire inator kit,
it is recommended to take your vehicle to your
dealer/retailer within 100 miles (161 kilometers) of
driving to have the tire inspected and repaired. If the
sealant is not removed from the tire within a 100 miles
(161 kilometers) of driving, it is more likely that the
tire and tire pressure monitoring sensor may get
damaged and have to be replaced.
5-87

Accessing the Tire Inator Kit
To access the tire inator kit:
1. Open the trunk. SeeTrunk on page 2-14for more
information.
2. Locate the tire inator kit by lifting up the carpet.
3. Remove the inator kit
cover by turning the
center nut
counterclockwise.
4. Remove the inator kit by pulling it straight out of
the foam container.
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Tire Sealant
The kit contains a liquid sealant that when injected into
a at tire, may temporarily repair nail holes or cuts in the
tread area of the tire. The tire sealant cannot repair tire
damage caused while driving on a at tire or a tire that
has had a “blow out” or a tire that has punctures in the
sidewall areas. The tire sealant solution is to be used for
a single tire and can only be used once.
Check the tire sealant expiration date on the sealant
canister. The sealant may not be as effective beyond the
expiration date. If needed, see your dealer/retailer for
a replacement canister.
After temporarily repairing a tire using the tire sealant,
take your vehicle to your dealer/retailer to have the
tire inspected and repaired.
Using the Tire Inator Kit
To use the tire inator kit:
1. Place the inator kit on the ground and unwrap the
sealant lling hose from the compressor.
2. Remove the air compressor accessory plug from
the unit. To do this, pull the top portion of the
wrapped cord out rst, then the bottom, then unsnap
the plug. Do not insert the plug into an accessory
outlet yet.
3. Remove the valve stem cap from the at tire by
turning it counterclockwise.
If an object, such as a nail, has penetrated the tire,
do not remove it.
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4. Attach the sealant lling hose (A) onto the tire valve
stem. Turn it clockwise until it is tight.
Make sure the inator kit on/off switch (B) is in the
O (off) position.
5. Plug the air compressor accessory plug (C) into an
accessory power outlet in the vehicle. See
Accessory Power Outlet(s) on page 3-26for more
information.
{CAUTION:
Idling the engine in a closed-in place or with
the climate control system off can cause
deadly carbon monoxide (CO). SeeEngine
Exhaust on page 2-36.
6. Start the vehicle. SeeStarting the Engine on
page 2-25for more information. The vehicle must be
running while using the air compressor.
{CAUTION:
Inating something too much can make it
explode, and you or others could be injured.
Be sure to read the inator instructions, and
inate the tire to its recommended pressure.
Do not exceed 36 psi (248 kPa).
7. Move the inator kit switch to the I (on) position.
The inator kit will force sealant and air into the
tire. Sealant may leak from the puncture hole until
the vehicle is driven and the hole has sealed.
5-90