Tires PONTIAC GRAND PRIX 2008 Owner's Manual

Trailer Brakes
Does your trailer have its own brakes? Be sure to read
and follow the instructions for the trailer brakes so
you’ll be able to install, adjust and maintain them
properly.
If your vehicle has anti-lock brakes, do not try to
tap into your vehicle’s brake system. If you do,
both brake systems won’t work well, or at all.
Even if your vehicle doesn’t have anti-lock brakes,
don’t tap into your vehicle’s brake system if the
trailer’s brake system will use more than
0.02 cubic inch (0.3 cc) of uid from your vehicle’s
master cylinder. If it does, both braking systems
won’t work well. You could even lose your brakes.
Will the trailer brake parts take 3,000 psi
(20 650 kPa) of pressure? If not, the trailer brake
system must not be used with your vehicle.
If everything checks out this far, then make the
brake uid tap at the upper rear master cylinder
port. But don’t use copper tubing for this. If you do,
it will bend and break off. Use steel brake tubing.
Driving with a Trailer
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, get to know the rig.
Acquaint yourself with the feel of handling and braking
with the added weight of the trailer. And always keep in
mind that the vehicle is now a good deal longer and not
nearly as responsive as the vehicle is by itself.
Before starting, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires, and mirror adjustment. If the trailer has
electric brakes, start the vehicle and trailer moving
and then apply the trailer brake controller by hand to
be sure the brakes are working. This lets you check
the electrical connection at the same time.
During your trip, check occasionally to be sure that
the load is secure, and that the lamps and any
trailer brakes are still working.
4-33

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of Your
Vehicle......................................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-24
Pressure Cap...............................................5-27
Engine Overheating.......................................5-27Overheated Engine Protection
Operating Mode........................................5-29
Cooling System............................................5-30
Power Steering Fluid.....................................5-39
Windshield Washer Fluid................................5-40
Brakes........................................................5-41
Battery........................................................5-45
Jump Starting...............................................5-46
Headlamp Aiming...........................................5-51
Bulb Replacement..........................................5-54
Halogen Bulbs..............................................5-54
Headlamps and Sidemarker Lamps.................5-54
Front Turn Signal, Parking and Fog Lamps......5-57
Taillamps, Turn Signal, and Stoplamps............5-58
Back-Up Lamps............................................5-59
License Plate Lamp......................................5-60
Replacement Bulbs.......................................5-60
Windshield Replacement.................................5-61
Windshield Wiper Blade Replacement..............5-61
Tires..............................................................5-62
Tire Sidewall Labeling...................................5-63
Tire Terminology and Denitions.....................5-66
Ination - Tire Pressure.................................5-69
Tire Pressure Monitor System.........................5-71
Section 5 Service and Appearance Care
5-1

Tire Pressure Monitor Operation.....................5-72
Tire Inspection and Rotation...........................5-75
When It Is Time for New Tires.......................5-77
Buying New Tires.........................................5-78
Different Size Tires and Wheels......................5-80
Uniform Tire Quality Grading..........................5-80
Wheel Alignment and Tire Balance..................5-82
Wheel Replacement......................................5-82
Tire Chains..................................................5-84
If a Tire Goes Flat........................................5-85
Tire Sealant and Compressor Kit (GXP)...........5-86
Changing a Flat Tire.....................................5-96
Removing the Spare Tire and Tools................5-98
Removing the Flat Tire and Installing the
Spare Tire..............................................5-100
Storing a Flat or Spare Tire and Tools...........5-107
Compact Spare Tire....................................5-109
Appearance Care..........................................5-109
Interior Cleaning.........................................5-109
Fabric/Carpet..............................................5-111
Leather......................................................5-112
Ultra Lux Suede..........................................5-113
Instrument Panel, Vinyl, and Other Plastic
Surfaces.................................................5-113
Care of Safety Belts....................................5-114Weatherstrips.............................................5-114
Washing Your Vehicle..................................5-114
Cleaning Exterior Lamps/Lenses....................5-115
Finish Care................................................5-115
Windshield and Wiper Blades.......................5-116
Aluminum Wheels.......................................5-116
Tires.........................................................5-117
Sheet Metal Damage...................................5-117
Finish Damage...........................................5-117
Underbody Maintenance...............................5-117
Chemical Paint Spotting...............................5-118
Vehicle Care/Appearance Materials................5-118
Vehicle Identication.....................................5-119
Vehicle Identication Number (VIN)................5-119
Service Parts Identication Label...................5-120
Electrical System..........................................5-120
Add-On Electrical Equipment.........................5-120
Headlamp Wiring........................................5-120
Windshield Wiper Fuses...............................5-121
Power Windows and Other Power Options......5-121
Fuses and Circuit Breakers..........................5-121
Instrument Panel Fuse Block........................5-122
Underhood Fuse Block................................5-124
Capacities and Specications........................5-128
Section 5 Service and Appearance Care
5-2

Brake Wear
Your vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads are
needed. The sound can come and go or be heard all the
time your vehicle is moving, except when you are pushing
on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specications in
Capacities and Specifications on page 5-128.
Brake linings should always be replaced as complete
axle sets.
5-43

Headlamp Aiming
The visual optical headlamp aiming system has been
preset at the factory and should need no further
adjustment.
However, If the vehicle is damaged in an accident, the
headlamp aim may be affected and adjustment may
be necessary.
If oncoming vehicles ash their high beams at you, this
may also mean the vertical aim needs to be adjusted.
It is recommended that the vehicle is taken to your
dealer/retailer for service if the headlamps need to be
re-aimed. It is possible however, to re-aim the
headlamps as described in the following procedure.The vehicle should be properly prepared as follows:The vehicle should be placed so the headlamps are
25 ft. (7.6 m) from a light colored wall.
The vehicle must have all four tires on a perfectly
level surface which is level all the way to the wall.
The vehicle should be placed so it is perpendicular
to the wall.
The vehicle should not have any snow, ice, or
mudonit.
The vehicle should be fully assembled and all other
work stopped while headlamp aiming is being done.
The vehicle should be normally loaded with a
full tank of fuel and one person or 160 lbs (75 kg)
sitting on the driver’s seat.
Tires should be properly inated.
5-51

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 vehicle Warranty
booklet for details.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much exing. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 4-22.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated 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 vehicle’s tires are cold. See
Inflation - Tire Pressure on page 5-69.
Overinated 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 the tire’s tread is badly worn, or if
your vehicle’s tires have been
damaged, replace them.
5-62

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
vehicle 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.(A) Tire Size
:The tire size is a combination of
letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction type,
and service description. See the “Tire Size”
illustration later in this section for more detail.
(B) 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.Passenger (P-Metric) Tire Example
5-63

(C) DOT (Department of Transportation):The
Department of Transportation (DOT) code indicates
that the tire is in compliance with the U.S.
Department of Transportation Motor Vehicle Safety
Standards.
(D) Tire Identication Number (TIN)
:The letters
and numbers following DOT (Department of
Transportation) code is the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides of
the tire, although only one side may have the date
of manufacture.
(E) Tire Ply Material
:The type of cord and
number of plies in the sidewall and under the tread.
(F) Uniform Tire Quality Grading (UTQG)
:Tire
manufacturers are required to grade tires based on
three performance factors: treadwear, traction, and
temperature resistance. For more information see
Uniform Tire Quality Grading on page 5-80.
(G) Maximum Cold Ination Load Limit
:Maximum load that can be carried and the
maximum pressure needed to support that load.(A) Temporary Use Only
:The compact spare
tire or temporary use tire has a tread life of
approximately 3,000 miles (5 000 km) and should
not be driven at speeds over 65 mph (105 km/h).
The compact spare tire is for emergency use when
a regular road tire has lost air and gone at. If your
vehicle has a compact spare tire, seeCompact
Spare Tire on page 5-109andIf a Tire Goes Flat on
page 5-85. Compact Spare Tire Example
5-64

(B) Tire Ply Material:The type of cord and
number of plies in the sidewall and under
the tread.
(C) Tire Identication Number (TIN)
:The letters
and numbers following the DOT (Department of
Transportation) code is the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides of
the tire, although only one side may have the date
of manufacture.
(D) Maximum Cold Ination Load Limit
:Maximum load that can be carried and the
maximum pressure needed to support that load.
(E) Tire Ination
:The temporary use tire or
compact spare tire should be inated to 60 psi
(420 kPa). For more information on tire pressure
and ination seeInflation - Tire Pressure on
page 5-69.
(F) Tire Size
:A combination of letters and
numbers dene a tire’s width, height, aspect ratio,
construction type, and service description. The
letter T as the rst character in the tire size means
the tire is for temporary use only.(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.
5-65

Treadwear Indicators:Narrow bands, sometimes
called wear bars, that show across the tread of
a tire when only 1/16 inch (1.6 mm) of tread
remains. SeeWhen It Is Time for New Tires on
page 5-77.
UTQGS (Uniform Tire Quality Grading
Standards)
:A tire information system that
provides consumers with ratings for a tire’s
traction, temperature, and treadwear. Ratings are
determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 5-80.
Vehicle Capacity Weight
:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading
Your Vehicle on page 4-22.
Vehicle Maximum Load on the Tire
:Load on an
individual tire due to curb weight, accessory
weight, occupant weight, and cargo weight.
Vehicle Placard
:A label permanently attached to
a vehicle showing the vehicle’s capacity weight
and the original equipment tire size and
recommended ination pressure. See “Tire and
Loading Information Label” underLoading
Your Vehicle on page 4-22.
Ination - Tire Pressure
Tires need the correct amount of air pressure to
operate effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is
not. If your tires do not have enough air
(under-ination), you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
5-69