2008 PONTIAC GRAND PRIX Owners Manual

9. Replace with a new bulb into the socket and turn
the lamp socket clockwise to install it.
10. Reinstall the taillamp assembly by reversing
Steps 2 through 5.
Back-Up Lamps
The back-up lamps are located on the trunk lid.
To replace the back-up lamp bulb(s):
1. Open the trunk. SeeTrunk on page 2-14for more
information.2. Turn the appropriate lamp socket a quarter turn
counterclockwise and remove it.
3. Remove the old bulb.
4. Put the new bulb into the lamp socket.
5. Turn the bulb a quarter turn clockwise to reinstall it.
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License Plate Lamp
To replace one of these bulbs:
1. Open the trunk. SeeTrunk on page 2-14
2. Turn the appropriate lamp socket a quarter turn
counterclockwise and remove it.
3. Remove the old bulb.
4. Put the new bulb into the lamp socket.
5. Turn the bulb a quarter turn clockwise to reinstall it.
Replacement Bulbs
Exterior Lamps Bulb Number
Back-Up Lamp 3157
Front Parking/Turn Signal Lamp3757 NAK* or
5702 KA**
Front Sidemarker and License
Plate Lamp194
Headlamps
High-Beam Halogen 9005
Low-Beam Halogen 9006
Stop/Taillamp/Turn Signal Lamps 3057
* Base Models with the Optional Fog Lamps
** For Lamps Not Equipped with the Fog Function and
GXP Models
For replacement bulbs not listed here, contact your
dealer/retailer.
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Windshield Replacement
If your vehicle is equipped with the Head-Up Display
(HUD) system, keep in mind that your windshield is part
of the HUD system. If you ever have to get your
windshield replaced, be sure to get one that is designed
for HUD or your HUD image may look blurred or out
of focus.
Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected for wear
or cracking. SeeScheduled Maintenance on page 6-4
for more information on wiper blade inspection.Replacement blades come in different types and are
removed in different ways. For the proper type and
length, seeMaintenance Replacement Parts on
page 6-13. Here is how to remove the wiper blade:
1. Pull the windshield wiper arm connector away from
the windshield.
2. While holding the wiper arm, pull the clip up from
the blade connecting point, and pull the blade
assembly down toward the windshield to remove it
from the wiper arm.
3. Install the new wiper blade onto the wiper arm and
snap the clip into place.
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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.
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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
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(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
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(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.
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(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.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
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