2007 PONTIAC GRAND PRIX wheel size

If the word OFF or the off symbol is lit on the
airbag status indicator, it means that the
passenger sensing system has turned off the right
front passenger’s frontal airbag. SeePassenger
Sensing System on page 74for more on this,
including important safety information.
If, after several seconds, all status indicator lights
remain on, or if there are no lights at all, there
may be a problem with the lights or the passenger
sensing system. See your dealer for service.
{CAUTION:
If the off indicator and the airbag
readiness light ever come on together, it
means that something may be wrong with
the airbag system. If this ever happens,
have the vehicle serviced promptly,
because an adult-size person sitting in the
right front passenger seat may not have
the protection of the frontal airbag. See
Airbag Readiness Light on page 172.
Up-Shift Light
If your vehicle has this
light, it will come on
when the shift lever is in
the manual transaxle
position.
It will appear as a prompt to up-shift to the next
gear using one of the Tap-Shift
®paddles located
on the steering wheel.
If your vehicle has the Head-Up Display (HUD), it
will only appear on it.
SeeAutomatic Transaxle Operation on page 110
andHead-Up Display (HUD) on page 151for
more information.
175

Windshield Wiper Blade Replacement....... 399
Tires............................................................ 400
Tire Sidewall Labeling............................... 401
Tire Terminology and Denitions............... 405
Ination - Tire Pressure............................. 408
Tire Pressure Monitor System................... 409
Tire Inspection and Rotation...................... 414
When It Is Time for New Tires.................. 415
Buying New Tires...................................... 416
Different Size Tires and Wheels................ 417
Uniform Tire Quality Grading..................... 418
Wheel Alignment and Tire Balance............ 419
Wheel Replacement.................................. 419
Tire Chains............................................... 421
If a Tire Goes Flat.................................... 422
Tire Inator Kit (GXP)................................ 424
Changing a Flat Tire................................. 435
Removing the Spare Tire and Tools.......... 436
Removing the Flat Tire and Installing the
Spare Tire............................................. 438
Storing a Flat or Spare Tire and Tools...... 445
Compact Spare Tire.................................. 447Appearance Care........................................ 448
Cleaning the Inside of Your Vehicle.......... 448
Fabric/Carpet............................................. 449
Leather...................................................... 451
Ultra Lux Suede........................................ 451
Instrument Panel, Vinyl, and Other Plastic
Surfaces................................................ 452
Care of Safety Belts.................................. 452
Weatherstrips............................................ 452
Washing Your Vehicle............................... 453
Cleaning Exterior Lamps/Lenses................ 453
Finish Care............................................... 453
Windshield and Wiper Blades.................... 454
Aluminum Wheels...................................... 454
Tires......................................................... 455
Sheet Metal Damage................................. 455
Finish Damage.......................................... 456
Underbody Maintenance............................ 456
Chemical Paint Spotting............................ 456
Vehicle Care/Appearance Materials............ 457
Section 5 Service and Appearance Care
334

Low-Prole Performance Tire (GXP)
If your vehicle has P255/45R18 size tires on the
front wheels and P225/50R18 size tires on the rear
wheels, they are classied as low-prole
performance tires. These tires are designed for
very responsive driving on wet or dry pavement.
You may also notice more road noise with
low-prole performance tires and that they tend to
wear faster.
Notice:If your vehicle has low-prole tires,
they are more susceptible to damage from road
hazards or curb impact than standard prole
tires. Tire and/or wheel assembly damage
can occur when coming into contact with road
hazards like, potholes, or sharp edged
objects, or when sliding into a curb. Your GM
warranty does not cover this type of damage.
Keep tires set to the correct ination pressure
and, when possible avoid contact with
curbs, potholes, and other road hazards.
Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The examples below show a typical
passenger vehicle tire and a compact spare tire
sidewall.
Passenger (P-Metric) Tire Example
401

(G) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
Tire Size
The following illustration shows an example of a
typical passenger vehicle tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P
as the rst character in the tire size means a
passenger vehicle tire engineered to standards set
by the U.S. Tire and Rim Association.
(B) Tire Width:The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.(C) Aspect Ratio:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 60,
as shown in item C of the illustration, it would
mean that the tire’s sidewall is 60 percent as high
as it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction;
the letter D means diagonal or bias ply
construction; and the letter B means belted-bias
ply construction.
(E) Rim Diameter:Diameter of the wheel in
inches.
(F) Service Description:These characters
represent the load range and speed rating of the
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certied to carry a
load. Speed ratings range from A to Z.
404

Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the
system is not operating properly. The TPMS
malfunction indicator is combined with the low tire
pressure telltale. When the system detects a
malfunction, the telltale will ash for approximately
one minute and then remain continuously
illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low
tire pressure as intended. TPMS malfunctions may
occur for a variety of reasons, including the
installation of replacement or alternate tires or
wheels on the vehicle that prevent the TPMS from
functioning properly. Always check the TPMS
malfunction telltale after replacing one or more
tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.
A Tire and Loading Information label, attached to
your vehicle, shows the size of your vehicle’s
original equipment tires and the correct ination
pressure for your vehicle’s tires when they are cold.SeeLoading Your Vehicle on page 317, for an
example of the Tire and Loading Information
label and its location on your vehicle. Also see
Ination - Tire Pressure on page 408.
Your vehicle’s TPMS system can warn you about
a low tire pressure condition but it does not
replace normal tire maintenance. SeeTire
Inspection and Rotation on page 414andTires on
page 400.
Notice:Do not use a tire sealant if your
vehicle has Tire Pressure Monitors. The liquid
sealant can damage the tire pressure monitor
sensors.
The TPMS will not function properly if one or more
of the TPMS sensors are missing or inoperable.
If the system detects a missing or inoperable
sensor, an error message SERVICE TIRE
MONITOR SYSTEM appears on the DIC display.
If you have replaced a tire/wheel assembly
without transferring the TPMS sensors, the error
message displays. Once you re-install the
TPMS sensors, the error message should go off.
See your dealer for service if all TPMS sensors
are installed and the error message comes on and
stays on.
411

Tire Inspection and Rotation
Tire rotation is not recommended if your vehicle is
a GXP model equipped with P255/45R18 size
tires on the front wheels and P225/50R18 size tires
on the rear wheels. Different tire sizes front to
rear should not be rotated.
Tire rotation is recommended if the original
equipment tires installed on your vehicle are
of the same size and type on all four tire/wheel
positions. Original equipment tires of the
same size and type should be rotated every
5,000 to 8,000 miles (8 000 to 13 000 km).
Any time you notice unusual wear, rotate your
vehicle’s tires as soon as possible and check the
wheel alignment. Also check for damaged tires
or wheels. SeeWhen It Is Time for New Tires on
page 415andWheel Replacement on page 419
for more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The
rst rotation is the most important. SeeScheduled
Maintenance on page 473for scheduled rotation
intervals.The correct rotation pattern shown here is only for
non-GXP tires.
Do not include the compact spare tire, if equipped,
in your vehicle’s tire rotation.
After the tires have been rotated, adjust the front
and rear ination pressures as shown on the Tire
and Loading Information label, and reset the Tire
Pressure Monitor System. SeeTire Pressure
Monitor System on page 409for additional
information.
Rotation Pattern for Non-GXP Tires Only
414

Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specications on page 466.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after 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 needed, to get all the rust or dirt
off. SeeChanging a Flat Tire on page 435.
When It Is Time for 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 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 cannot be repaired well because of the
size or location of the damage.
415

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 by the tire manufacturer.
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 401for additional information.{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. SeeCompact Spare Tire on
page 447.
416