2009 PONTIAC G8 tires

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 inCapacities and
Specifications on page 10-2.
Brake linings should always be
replaced as complete axle sets.Brake Pedal Travel
See your dealer/retailer if the brake
pedal does not return to normal
height, or if there is a rapid increase
in pedal travel. This could be a
sign that brake service might
be required.
Brake Adjustment
Every time he brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle
is complex. Its many parts have
to be of top quality and work
well together if the vehicle is
to have really good braking.The vehicle was designed and
tested with top-quality brake parts.
When parts of the braking system
are replaced — for example,
when the brake linings wear
down and new ones are
installed — be sure to get new
approved replacement parts. If this
is not done, the brakes might
not work properly. For example,
if someone puts in brake linings that
are wrong for the vehicle, the
balance between the front and rear
brakes can change — for the
worse. The braking performance
expected can change in many other
ways if the wrong replacement
brake parts are installed.
Vehicle Service and Care 9-27

The vehicle should:
Be placed so the headlamps
are 25 ft. (7.6 m) from a light
colored wall.
Have all four tires on a perfectly
level surface which is level all
the way to the wall.
Be placed so it is at a right angle
to the wall.
Not have any snow, ice, or
mudonit.
Be fully assembled and all other
work stopped while headlamp
aiming is being done.
Have a full tank of fuel and one
person or 160 lbs (75 kg) on
the driver seat.
Have all tires properly inated.
Headlamp aiming is done with
the vehicle’s low-beam headlamps.
The high-beam headlamps will
be correctly aimed if the low-beam
headlamps are aimed properly.To adjust the vertical aim on the
headlamps:
1. Open the hood.Hood Release
on page 9-5.
2. Locate the aim dot on the lens of
the low-beam headlamp.
3. Record the distance from the
ground to the aim dot on the
low-beam headlamp.4. At the wall, measure from the
ground upward (A) to the
recorded distance from Step 3
and mark it.
5. Draw or tape a horizontal line (B)
on the wall the width of the
vehicle at the height of the
mark in Step 4.
Vehicle Service and Care 9-29

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.
SeeLoading the Vehicle
on page 8-30.
(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.
SeeInflation - Tire
Pressure on page 9-49.
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.
(Continued)
CAUTION (Continued)
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.
Tire Sidewall Labeling
Useful information about a tire
is molded into its sidewall.
The examples show a typical
passenger vehicle tire and
a compact spare tire sidewall.
9-42 Vehicle Service and Care

(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.
(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
seeUniform Tire Quality
Grading on page 9-62.
(G) Maximum Cold Ination
Load Limit
:Maximum load
that can be carried and the
maximum pressure needed to
support that load.
Passenger (P-Metric) Tire
Example
Vehicle Service and Care 9-43

(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 9-83andIf a Tire
Goes Flat on page 9-66.
(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 see
Inflation - Tire Pressure on
page 9-49.
(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.
Compact Spare Tire Example
9-44 Vehicle Service and Care

Radial Ply Tire:A pneumatic
tire in which the ply cords that
extend to the beads are laid
at 90 degrees to the centerline
of the tread.
Rim
:A metal support for a
tire and upon which the
tire beads are seated.
Sidewall
:The portion of a tire
between the tread and the bead.
Speed Rating
:An alphanumeric
code assigned to a tire
indicating the maximum speed
at which a tire can operate.
Traction
:The friction between
the tire and the road surface.
The amount of grip provided.
Tread
:The portion of a tire that
comes into contact with the road.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 9-59.
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 9-62.Vehicle Capacity Weight
:The number of designated
seating positions multiplied
by 150 lbs (68 kg) plus the rated
cargo load. SeeLoading the
Vehicle on page 8-30.
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” under
Loading the Vehicle on
page 8-30.
9-48 Vehicle Service and Care

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 economyIf your tires have too much air
(over-ination), you can get
the following:
 Unusual wear
 Poor handling
 Rough ride
 Needless damage from
road hazards
A vehicle specic Tire and
Loading Information label is
attached to the vehicle’s center
pillar, below the driver’s door
latch. This label lists the
vehicle’s original equipment tires
and the recommended cold
tire ination pressure for the tires
when they are cold. The
recommended cold tire ination
pressure, shown on the label,is the minimum amount of air
pressure needed to support your
vehicle’s maximum load
carrying capacity. For more
information regarding how much
weight your vehicle can carry,
seeLoading the Vehicle on
page 8-30.
How you load your vehicle
affects vehicle handling and ride
comfort. When driving with
less than the maximum load
capacity allowed for your vehicle,
you can set tire ination
pressure to the recommended
amounts shown in the following
chart. Never load your vehicle
with more weight than it
was designed to carry.
Vehicle Service and Care 9-49

Tire SizeRecommended Cold Tire Ination
Occupant and Cargo Weight: 573 lbs (260 kg) or Less Occupant and Cargo Weight:
Up to 917 lbs (416 kg)
(Vehicle Capacity Weight)
Front Tires Rear Tires Front Tires Rear Tires
P245/45R18 96V 33 psi (230 kPa) 33 psi (230 kPa) 36 psi (250 kPa) 39 psi (270 kPa) 245/45R18 96V 36 psi (250 kPa) 36 psi (250 kPa) 36 psi (250 kPa) 39 psi (270 kPa)
245/40R19 94W 36 psi (250 kPa) 36 psi (250 kPa
)36 psi (250 kPa) 39 psi (270 kPa)
T155/80R17 111M (Compact Spare) 60 psi (420 kPa) 60 psi (420 kPa) 60 psi (420 kPa) 60 psi (420 kPa)
When to Check
Check your tires once a month
or more.
Do not forget the compact spare
tire, if your vehicle has one. It
should be at 60 psi (420 kPa).
For more information about
the vehicle’s compact spare tire,
see Compact Spare Tire on
page 9-83 . How to Check
Use a good quality pocket-type
gage to check tire pressure.
You can’t tell if your tires
are properly inated simply by
looking at them. Radial tires may
look properly inated even
when they’re underinated.
Check the tire’s ination
pressure when the tires are
cold. Cold means your vehicle
has been sitting for at least three
hours or driven no more than
1 mile (1.6 km). Remove the valve cap from the
tire valve stem. Press the
tire gage rmly onto the valve to
get a pressure measurement.
If the cold tire ination pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the ination pressure is
low, add air until you reach the
recommended amount.
9-50 Vehicle Service and Care