brake PONTIAC G8 2009 Service Manual

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.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in pounds per square
inch (psi) or kilopascals (kPa)
before a tire has built up heat
from driving. SeeInflation - Tire
Pressure on page 9-49.Curb Weight
:The weight of a
motor vehicle with standard
and optional equipment including
the maximum capacity of fuel,
oil, and coolant, but without
passengers and cargo.
DOT Markings
:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) motor vehicle safety
standards. The DOT code
includes the Tire Identication
Number (TIN), an alphanumeric
designator which can also
identify the tire manufacturer,
production plant, brand, and date
of production.
GVWR
:Gross Vehicle Weight
Rating. SeeLoading the Vehicle
on page 8-30.
9-46 Vehicle Service and Care

If the TPMS is not functioning it
cannot detect or signal a low
tire condition. See the dealer/retailer
for service if the TPMS malfunction
light and DIC message comes
on and stays on.
TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identication code. Any time one or
more of the TPMS sensors are
replaced or the vehicle’s tires are
rotated, the identication codes
need to be matched to the
new tire/wheel location. The sensors
are matched, to the tire/wheel
locations, in the following order:
driver side front tire, passenger side
front tire, passenger side rear
tire, and driver side rear tire using a
TPMS diagnostic tool. See your
dealer/retailer for service.The TPMS sensors can also be
matched to each tire/wheel position
by increasing or decreasing the
tire’s air pressure. When increasing
the tire’s pressure, do not exceed
the maximum ination pressure
indicated on the tire’s sidewall. To
decrease the tire’s air-pressure
use the pointed end of the valve
cap, a pencil-style air pressure
gage, or a key.
You have two minutes to match
each tire and wheel position.
If it takes longer than two minutes to
match any tire and wheel position,
the matching process stops and you
need to start over.
The TPMS matching process is
outlined below:
1. Set the parking brake.
2. Turn the ignition switch to
ON/RUN with the engine off.
3. Press and hold the Remote
Keyless Entry (RKE) transmitter’s
lock and unlock buttons, at the
same time, for about ve secondsto start the TPMS learn mode.
The horn chirps two times
indicating the TPMS receiver is
ready and in learn mode.
4. Start with the driver side front
tire. The driver side front
indicator lamp also comes on to
indicate that corner’s sensor
is ready to be learned.
5. Remove the valve cap from the
tire’s valve stem. Activate the
TPMS sensor by increasing
or decreasing the tire’s air
pressure for about eight seconds.
The horn chirps one time to
conrm the sensor identication
code has been matched to
the tire/wheel position.
9-56 Vehicle Service and Care

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 9-42for 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 9-57for
information on proper tire rotation.{CAUTION
Mixing tires could cause you
to lose control while driving. If
you mix tires of different sizes,
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, brands,
or types may also cause
damage to the vehicle. Be
sure to use the correct size,
brand, and type of tires on all
wheels. It is all right to drive
with the compact spare
temporarily, as it was
developed for use on the
vehicle. SeeCompact Spare
Tire on page 9-83.{CAUTION
If you use bias-ply tires on the
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 the 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.
9-60 Vehicle Service and Care

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 9-52.
Your vehicle’s original equipment
tires are listed on the Tire and
Loading Information Label. See
Loading the Vehicle on page 8-30,
for more information about the
Tire and Loading Information Label
and its location on your vehicle.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, antilock
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 9-59
andAccessories and Modifications
on page 9-3for additional
information.
Vehicle Service and Care 9-61

Wheel Alignment and
Tire Balance
The tires and wheels on your vehicle
were aligned and balanced carefully
at the factory to give you the longest
tire life and best overall performance.
Adjustments to wheel alignment and
tire balancing will not be necessary
on a regular basis. However, if you
notice unusual tire wear or your
vehicle pulling to one side or the
other, the alignment might need to be
checked. If you notice your vehicle
vibrating when driving on a smooth
road, the tires and wheels might
need to be rebalanced. See your
dealer/retailer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked or badly rusted or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts
should be replaced. If the wheel
leaks air, replace it (except some
aluminum wheels, which can
sometimes be repaired). See your
dealer/retailer if any of these
conditions exist.
Your dealer/retailer will know the
kind of wheel you need.
Each new wheel should have
the same load-carrying capacity,
diameter, width, offset and be
mounted the same way as the
one it replaces.
If you need to replace any of the
wheels, wheel bolts or wheel
nuts, replace them only with new
GM original equipment parts.
This way, you will be sure to have
the right wheel, wheel bolts and
wheel nuts for the vehicle.{CAUTION
Using the wrong replacement
wheels, wheel bolts, or wheel nuts
on your vehicle can be dangerous.
It could affect the braking and
handling of your vehicle, make
your tires lose air and make you
lose control. You could have a
collision in which you or others
could be injured. Always use the
correct wheel, wheel bolts, and
wheel nuts for replacement.
Notice:The wrong wheel can
also cause problems with bearing
life, brake cooling, speedometer
or odometer calibration, headlamp
aim, bumper height, vehicle
ground clearance, and tire or tire
chain clearance to the body and
chassis.
SeeChanging a Flat Tire on
page 9-75for more information.
9-64 Vehicle Service and Care

Used Replacement Wheels
{CAUTION
Putting a used wheel on the
vehicle is dangerous. You cannot
know how it has been used or how
far it has been driven. It could fail
suddenly and cause a crash. If you
have to replace a wheel, use a
new GM original equipment wheel.
Tire Chains
{CAUTION
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 the vehicle and you or
others may be injured in a crash.
(Continued)
CAUTION (Continued)
Use another type of traction
device only if its manufacturer
recommends it for use on the
vehicle and tire size combination
and road conditions. Follow that
manufacturer’s instructions. To
help avoid damage to the vehicle,
drive slowly, readjust or remove
the device if it is contacting the
vehicle, and do not spin the
vehicle’s wheels. If you do nd
traction devices that will t, install
them on the front tires.
Vehicle Service and Care 9-65

Tire Changing
If a Tire Goes Flat
It is unusual for a tire to blowout
while you are driving, especially if
you maintain your tires properly. See
Tires on page 9-42. If air goes out of
a tire, It is much more likely to leak
out slowly. But if you should ever
have a blowout, here are a few tips
about what to expect and what to do:
If a front tire fails, the at tire will
create a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel rmly. Steer to
maintain lane position, and then
gently brake to a stop well out of the
traffic lane.A rear blowout, particularly on a
curve, acts much like a skid
and may require the same correction
you would use in a skid. In any
rear blowout, remove your foot from
the accelerator pedal. Get the
vehicle under control by steering the
way you want the vehicle to go. It
may be very bumpy and noisy,
but you can still steer. Gently brake
to a stop, well off the road if
possible.
If a tire goes at, and your vehicle
has a compact spare tire, see
Changing a Flat Tire on page 9-75.
This information shows you how
to use the vehicle’s tire changing
equipment and how to change a at
tire safely.
{CAUTION
Lifting a vehicle and getting under
it to do maintenance or repairs is
dangerous without the appropriate
safety equipment and training. If a
jack is provided with the vehicle, it
is designed only for changing a
at tire. If it is used for anything
else, you or others could be badly
injured or killed if the vehicle slips
off the jack. If a jack is provided
with the vehicle, only use it for
changing a at tire.
9-66 Vehicle Service and Care

Tire Sealant and
Compressor Kit
If your vehicle has a factory installed
Tire Sealant and Compressor kit,
there is no spare tire, no tire
changing equipment and no place
to store a tire.
If a tire goes at, avoid further tire
and wheel damage by driving slowly
to a level place and stopping.
1. Turn on the hazard warning
ashers. SeeHazard Warning
Flashers on page 4-4.
2. Park your vehicle. Set the
parking brake rmly and put the
shift lever in P (Park). See
Shifting Into Park (Automatic
Transmission) on page 8-12.3. Turn off the engine.
4. Inspect the at tire.
If the tire has been separated from
the wheel, has damaged sidewalls,
or has a puncture larger than a
14inch (6 mm), the tire is too
severely damaged for the tire
sealant and compressor kit to be
effective. SeeRoadside Assistance
Program on page 12-6.
If the tire has a puncture less than
a
14inch (6 mm) in the tread area
of the tire, seeTire Sealant and
Compressor Kit (V8 Engine) on
page 9-67.
Tire Sealant and
Compressor Kit
(V8 Engine)
This vehicle has a tire sealant and
compressor kit in place of a jack or
spare tire. It is located in a foam
container in the trunk. The tire
sealant and compressor kit can be
used to repair a at tire by sealing
small punctures in the tread of the
tire. It can also be used to inate an
underinated tire. The vehicle must
be driven for ve miles (8 kilometers)
after the tire is sealed and inated
to the recommended pressure to
ensure the sealant is distributed
evenly. For detailed instructions
see “Using the Tire Sealant and
Compressor Kit to Temporarily
Repair a Punctured Tire” later in
this section.
Vehicle Service and Care 9-67

Changing a Flat Tire
If a tire goes at, avoid further tire
and wheel damage by driving slowly
to a level place. Turn on the
hazard warning ashers.
{CAUTION
Changing a tire can be dangerous.
The vehicle can slip off the jack
and roll over or fall on you or other
people. You and they could be
badly injured or even killed. Find a
level place to change your tire.
To help prevent the vehicle from
moving:
1. Set the parking brake rmly.
2. Put an automatic
transmission shift lever in
P (Park), or shift a manual
transmission to 1 (First) or
R (Reverse).
(Continued)
CAUTION (Continued)
3. Turn off the engine and do
not restart while the vehicle
is raised.
4. Do not allow passengers to
remain in the vehicle.
To be certain the vehicle will not
move, put blocks at the front and
rear of the tire farthest away from
the one being changed. That
would be the tire on the other
side, at the opposite end of the
vehicle.When you have a at tire, place the
wheel block at the tire diagonally
across from the at tire.
Vehicle Service and Care 9-75

13. Lower the vehicle by turning the
jack handle counterclockwise.
Lower the jack completely.
14. Tighten the wheel nuts rmly in
a crisscross sequence, as
shown.{CAUTION
Incorrect or improperly tightened
wheel nuts can cause the wheel to
come loose and even come off.
This could lead to a crash. If you
have to replace them, be sure to
get new original equipment wheel
nuts. Stop somewhere as soon
as you can and have the nuts
tightened with a torque wrench to
the proper torque specication.
SeeCapacities and Specifications
on page 10-2for wheel nut torque
specication.Notice:Improperly tightened
wheel nuts can lead to brake
pulsation and rotor damage.
To avoid expensive brake repairs,
evenly tighten the wheel nuts
in the proper sequence and to
the proper torque specication.
SeeCapacities and Specifications
on page 10-2for the wheel nut
torque specication.
Vehicle Service and Care 9-81