tire size PONTIAC GRAND PRIX 2008 User Guide

When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions
inuence when you need new tires.
One way to tell when it is
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 new tires 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
cannot be repaired well because of the size or
location of the damage.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if
your vehicle has one. Multiple conditions affect how fast
this aging takes place, including temperatures, loading
conditions, and ination pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure about
the need to replace your tires as they get older, consult
the tire manufacturer for more information.
5-77

Buying New Tires
GM has developed and matched specic tires for
your vehicle. The original equipment tires installed
on your vehicle, when it was new, were designed to
meet General Motors Tire Performance Criteria
Specication (TPC Spec) system rating. If you need
replacement tires, GM strongly recommends that
you get tires with the same TPC Spec rating. This
way, your vehicle will continue to have tires that are
designed to give the same performance and vehicle
safety, during normal use, as the original tires.
GM’s exclusive TPC Spec system considers over
a dozen critical specications that impact the
overall performance of your vehicle, including brake
system performance, ride and handling, traction
control, and tire pressure monitoring performance.
GM’s TPC Spec number is molded onto the tire’s
sidewall near the tire size. If the tires have an
all-season tread design, the TPC Spec number will
be followed by an MS for mud and snow. SeeTire
Sidewall Labeling on page 5-63for additional
information.GM recommends replacing tires in sets of four.
This is because uniform tread depth on all tires will
help keep your vehicle performing most like it did
when the tires were new. Replacing less than a full
set of tires can affect the braking and handling
performance of your vehicle. SeeTire Inspection
and Rotation on page 5-75for information on
proper tire rotation.
{CAUTION:
Mixing tires could cause you to lose
control while driving. If you mix tires of
different sizes (other than those originally
installed on your vehicle), brands, or types
(radial and bias-belted tires), the vehicle
may not handle properly, and you could
have a crash. Using tires of different sizes
(other than those originally installed on
your vehicle) may also cause damage to
your vehicle. Be sure to use the correct
size, brand, and type tires on all wheels.
If your vehicle has a compact spare tire, it
is all right to drive your vehicle with the
compact spare temporarily. It was
developed for use on your vehicle. See
Compact Spare Tire on page 5-109.
5-78

{CAUTION:
If you use bias-ply tires on your vehicle,
the wheel rim anges 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.
If you must replace your vehicle’s tires with those
that do not have a TPC Spec number, make sure
they are the same size, load range, speed rating,
and construction type (radial and bias-belted tires)
as your vehicle’s original tires.Vehicles that have a tire pressure monitoring
system could give an inaccurate low-pressure
warning if non-TPC Spec rated tires are installed
on your vehicle. Non-TPC Spec rated tires may
give a low-pressure warning that is higher or lower
than the proper warning level you would get with
TPC Spec rated tires. SeeTire Pressure Monitor
System on page 5-71.
Your vehicle’s original equipment tires are listed
on the Tire and Loading Information Label.
SeeLoading Your Vehicle on page 4-22, for more
information about the Tire and Loading Information
Label and its location on your vehicle.
5-79

Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this may affect
the way your vehicle performs, including its braking, ride
and handling characteristics, stability, and resistance to
rollover. Additionally, if your vehicle has electronic
systems such as, anti-lock brakes, traction control, and
electronic stability control, the performance of these
systems can be affected.
{CAUTION:
If you add different sized wheels, your vehicle
may not provide an acceptable level of
performance and safety if tires not
recommended for those wheels are selected.
You may increase the chance that you will
crash and suffer serious injury. Only use GM
specic wheel and tire systems developed for
your vehicle, and have them properly installed
by a GM certied technician.
SeeBuying New Tires on page 5-78andAccessories
and Modifications on page 5-3for additional information.
Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration (NHTSA), 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 (UTQG)
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.
5-80

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

Storing a Flat or Spare Tire and
Tools
{CAUTION:
Storing a jack, a tire, or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision,
loose equipment could strike someone.
Store all these in the proper place.
After the compact spare tire is put on the vehicle, store
the at tire in the trunk. Use the following procedure
to secure it in the trunk. When storing a full-size tire, use
the extension and protector/guide, located in the foam
holder, to help avoid wheel surface damage.To store a full-size tire:
1. Install the tools in their original location in the trunk
area and secure.
2. Place the tire in the trunk with the valve stem facing
down, and the protector/guide placed through a
wheel bolt hole.
3. Remove the protector and attach the retainer
securely.
4. Place the protector/guide back in the foam holder
when putting the compact spare back in the trunk.
Store the cover as far forward as possible.
The compact spare tire is for temporary use only.
Replace the compact spare tire with a full-size tire as
soon as possible. SeeCompact Spare Tire on
page 5-109for more information. Use the following as a
guide for storing the compact spare tire and tools.
5-107

A. Retainer
B. Cover
C. Compact Spare Tire
D. Nut
E. Jack
F. Wheel Wrench
G. Extension and
Protective Guide
H. Foam Holder
I. Bolt ScrewA. Retainer
B. Spare Tire
C. Protector
D. Bolt Extension
E. Nut
F. Jack
G. Wheel Wrench
H. Foam Holder
I. Bolt Screw
Compact Spare Tire
Full-Sized Spare Tire
5-108

Compact Spare Tire
Although the compact spare tire was fully inated when
the vehicle was new, it can lose air after a time.
Check the ination pressure regularly. It should be
60 psi (420 kPa).
After installing the compact spare on the vehicle, you
should stop as soon as possible and make sure the
spare tire is correctly inated. The compact spare is
made to perform well at speeds up to 65 mph (105 km/h)
for distances up to 3,000 miles (5 000 km), so you can
nish your trip and have the full-size tire repaired or
replaced where you want. You must calibrate the tire
ination monitor system, if your vehicle has this feature,
after installing or removing the compact spare. SeeTire
Pressure Monitor System on page 5-71. The system may
not work correctly when the compact spare is installed on
the vehicle. Of course, it’s best to replace the spare with a
full-size tire as soon as you can. The spare will last longer
and be in good shape in case you need it again.
Notice:When the compact spare is installed, do
not take your vehicle through an automatic car wash
with guide rails. The compact spare can get
caught on the rails. That can damage the tire and
wheel, and maybe other parts of your vehicle.Do not use the compact spare on other vehicles.
And do not mix the compact spare tire or wheel with
other wheels or tires. They will not t. Keep the
spare tire and its wheel together.
Notice:Tire chains will not t your compact spare.
Using them can damage your vehicle and can
damage the chains too. Do not use tire chains on
your compact spare.
Appearance Care
Interior Cleaning
Your vehicle’s interior will continue to look its best if it is
cleaned often. Although not always visible, dust and dirt
can accumulate on your upholstery. Dirt can damage
carpet, fabric, leather, and plastic surfaces. Regular
vacuuming is recommended to remove particles from
your upholstery. It is important to keep your upholstery
from becoming and remaining heavily soiled. Soils should
be removed as quickly as possible. Your vehicle’s interior
may experience extremes of heat that could cause stains
to set rapidly.
Lighter colored interiors may require more frequent
cleaning. Use care because newspapers and garments
that transfer color to your home furnishings may also
transfer color to your vehicle’s interior.
5-109

Tires (cont.)
Different Size..............................................5-80
If a Tire Goes Flat.......................................5-85
Ination - Tire Pressure................................5-69
Inspection and Rotation................................5-75
Installing the Spare Tire..............................5-100
Pressure Monitor Operation...........................5-72
Pressure Monitor System..............................5-71
Removing the Flat Tire...............................5-100
Removing the Spare Tire and Tools...............5-98
Storing a Flat or Spare Tire and Tools..........5-107
Tire Sealant and Compressor Kit...................5-86
Tire Sidewall Labeling..................................5-63
Tire Terminology and Denitions....................5-66
Uniform Tire Quality Grading.........................5-80
Wheel Alignment and Tire Balance.................5-82
Wheel Replacement.....................................5-82
When It Is Time for New Tires......................5-77
Towing
Recreational Vehicle.....................................4-27
Towing a Trailer..........................................4-29
Your Vehicle...............................................4-27Traction
Control System (TCS).................................... 4-6
Control System Warning Light.......................3-47
Enhanced Traction System (ETS).................... 4-7
Enhanced Traction System (ETS)
Warning Light..........................................3-48
Stabilitrak
®Plus System................................. 4-8
Transmission
Fluid, Automatic...........................................5-22
Up-Shift Light..............................................3-45
Transmission Operation, Automatic....................2-28
Trunk............................................................2-14
Turn and Lane-Change Signals.......................... 3-8
Turn Signal/Multifunction Lever........................... 3-7
U
Uniform Tire Quality Grading............................5-80
Up-Shift Light.................................................3-45
Using this Manual............................................... iii
13

V
Vehicle
Control........................................................ 4-3
Damage Warnings........................................... iv
Loading......................................................4-22
Symbols......................................................... iv
Vehicle Customization, DIC..............................3-89
Vehicle Data Recording and Privacy..................7-16
Vehicle Identication
Number (VIN)............................................5-119
Service Parts Identication Label..................5-120
Vehicle, Remote Start....................................... 2-7
Ventilation Adjustment......................................3-36
Visors...........................................................2-18
W
Warning Lights, Gages and Indicators................3-38
Warnings
DIC Warnings and Messages........................3-67
Hazard Warning Flashers............................... 3-6
Other Warning Devices.................................. 3-6
Safety and Symbols......................................... iii
Vehicle Damage.............................................. ivWheels
Alignment and Tire Balance..........................5-82
Different Size..............................................5-80
Replacement...............................................5-82
Where to Put the Restraint...............................1-38
Windows.......................................................2-16
Power ........................................................2-17
Windshield
Replacement...............................................5-61
Washer Fluid..............................................5-40
Wiper Blade Replacement.............................5-61
Wiper Blades, Cleaning..............................5-116
Wiper Fuses.............................................5-121
Wiper Lever................................................3-10
Winter Driving................................................4-17X
XM Radio Messages.....................................3-114
XM™ Satellite Radio Antenna System..............3-118
Y
Your Vehicle and the Environment....................... 6-2
14