service PONTIAC G8 2008 Owners Manual

Uniform Tire Quality
Grading
Quality grades can be found
where applicable on the
tire sidewall between tread
shoulder and maximum section
width. For example:
Treadwear 200 Traction AA
Temperature A
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in
the United States. The gradesare molded on the sidewalls of
most passenger car tires. The
Uniform Tire Quality Grading
(UTQG) system does not apply to
deep tread, winter-type snow
tires, space-saver, or temporary
use spare tires, tires with nominal
rim diameters of 10 to 12 inches
(25 to 30 cm), or to some
limited-production tires.
While the tires available on
General Motors passenger cars
and light trucks may vary
with respect to these grades,
they must also conform to
federal safety requirements and
additional General Motors
Tire Performance Criteria (TPC)
standards.Treadwear
The treadwear grade is a
comparative rating based on the
wear rate of the tire when
tested under controlled
conditions on a specied
government test course. For
example, a tire graded
150 would wear one and a half
(1.5) times as well on the
government course as a tire
graded 100. The relative
performance of tires depends
upon the actual conditions
of their use, however, and may
depart signicantly from the
norm due to variations in driving
habits, service practices, and
differences in road
characteristics and climate.
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Traction – AA, A, B, C
The traction grades, from highest
to lowest, are AA, A, B, and
C. Those grades represent the
tire’s ability to stop on wet
pavement as measured under
controlled conditions on
specied government test
surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
{WARNING
The traction grade assigned
to this tire is based on
straight-ahead braking
traction tests, and does
not include acceleration,
cornering, hydroplaning, or
peak traction characteristics.Temperature – A, B, C
The temperature grades are A
(the highest), B, and C,
representing the tire’s resistance
to the generation of heat and
its ability to dissipate heat when
tested under controlled
conditions on a specied indoor
laboratory test wheel. Sustained
high temperature can cause
the material of the tire to
degenerate and reduce tire life,
and excessive temperature
can lead to sudden tire failure.
The grade C corresponds to
a level of performance which all
passenger car tires must
meet under the Federal Motor
Vehicle Safety Standard
No. 109. Grades B and A
represent higher levels of
performance on the laboratory
test wheel than the minimum
required by law.
{WARNING
The temperature grade for
this tire is established for a
tire that is properly inated
and not overloaded.
Excessive speed,
underination, or excessive
loading, either separately or
in combination, can cause
heat buildup and possible
tire failure.
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,
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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 (V6
Engine) on page 9-71for more
information.
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.
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2008 - Pontiac G8 Owner Manual

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.
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 9-39. 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.
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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 (V6 Engine) on
page 9-71. 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. The jack provided
with your vehicle 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. Use the jack provided with
your vehicle only for changing a
at tire.
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 PARK (P). See
Shifting Into Park (Automatic
Transmission) on page 8-10.
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 9-64.
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2008 - Pontiac G8 Owner Manual

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.The kit includes:
A. On/Off Switch
B. Air Compressor Accessory Plug
C. Air Compressor
D. Sealant Canister
E. Sealant/Air Hose
F. Air-only Hose
G. Pressure Gage
Tire Sealant
The sealant can temporarily seal a
small puncture up to 6 mm in
the tread area of the tire. The
sealant cannot seal sidewall
damage, large punctures, or a wheel
that has unseated from the wheel.
Read and follow the safe handling
instructions on the label adhered to
the sealant canister.
Check the tire sealant expiration
date on the sealant canister.
The sealant canister should be
replaced before its expiration date.
There is only enough sealant to
seal one tire. After usage, the
sealant canister and sealant/air hose
assembly must be replaced.
Replacement sealant canisters are
available from a dealer/retailer.
See “Removal and Installation of
Sealant Canister” later in this
section.
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2008 - Pontiac G8 Owner Manual

Using the Tire Sealant and
Compressor Kit to
Temporarily Seal and Inate a
Punctured Tire
Follow these directions closely for
correct sealant usage.
A. On/Off Switch
B. Air Compressor Accessory Plug
C. Air Compressor
D. Sealant Canister
E. Sealant/Air Hose
F. Air-only Hose
G. Pressure GageDo a safety check before
proceeding. SeeIf a Tire Goes Flat
on page 9-62.
Inspect the damaged tire.
The sealant cannot seal sidewall
damage, large punctures, or a
tire that has unseated from
the wheel. SeeRoadside Assistance
Program on page 12-6.
Do not remove any objects that
have penetrated the tire.
1. Place the tire sealant and
compressor kit on the ground and
unwrap the sealant/air hose (E)
from the side of the compressor.
2. Remove the air compressor
accessory plug (B) from the unit.
Do not plug the plug in yet.
3. Turn the tire valve stem cap
counterclockwise to remove.
4. Attach the sealant/air hose (E)
onto the tire valve stem. Turn
it clockwise until tight.5. Make sure the sealant and
compressor kit on/off switch (A) is
in the O (off) position.
Plug the air compressor
accessory plug (B) into an
accessory power outlet in the
vehicle. SeeAccessory Power
Outlet(s) on page 4-9for
more information.
Do not slam door or close
window on the compressor
accessory plug cord.
{CAUTION
Idling the engine in a closed-in
place or with the climate
control system off can cause
deadly carbon monoxide (CO).
SeeEngine Exhaust on
page 8-12.
6. Start the vehicle. The vehicle
must be running while using
the air compressor.
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2008 - Pontiac G8 Owner Manual

{CAUTION
Overination could cause the
tire to rupture, and you or
others could be injured. Be
sure to read the inator
instructions, and inate the tire
to its recommended pressure.
Do not exceed 36 psi (248 kPa).
7. Push the On/Off switch (A) to the
I (on) position.
The kit will begin to inject sealant
into the tire. Sealant could leak
from the puncture hole until
the vehicle is driven and the hole
has sealed.
8. Check the air pressure gage (G).
If there is not a pressure reading
while the compressor is
running, check for leaks at the
connection between the tire valve
stem and the sealant/air
hose (E).9. Inate the tire to the
recommended ination
pressure, found on the Tire
and Loading Information label.
SeeInflation - Tire Pressure
on page 9-46.
The pressure gage (G) will
initially read high while the
compressor injects the sealant
into the tire. Once the sealant
injection is complete, the
pressure will quickly drop. It will
start to rise again as the tire
inates with air.
10. Turn the compressor off by
pushing the On/Off button (A)
to the I (off) position.
The pressure gage (G) reads
slightly high while the
compressor is on. Turn the
compressor off to get an
accurate reading. The
compressor may be turned on
and off until the correct pressure
is reached.Notice:If the recommended
pressure cannot be reached after
approximately 15 minutes, the
vehicle should not be driven. The
tire is too severely damaged
and the tire sealant and
compressor kit cannot inate the
tire. Remove the air compressor
accessory plug from the
accessory power outlet and
unscrew the sealant/air hose from
the tire valve or tire pressure
monitoring sensor valve.
SeeRoadside Assistance
Program on page 12-6.
The tire is not sealed and will
continue to leak air until the
vehicle is driven and the sealant
is distributed in the tire.
Steps 11 through 19 must be
done right after Step 10.
Be careful while handling the tire
sealant and compressor kit as
they could be hot after usage.
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11. Unplug the air compressor
accessory plug (B) from the
accessory power outlet in
the vehicle.
12. Turn the sealant/air hose (E)
counterclockwise to remove.
13. Replace the tire valve
stem cap.
14. Stow the sealant/air hose (E)
and air compressor accessory
plug (B) in their original
locations.
15. If the at tire was able to be
inated to the recommended
ination pressure, remove
the maximum speed label from
the sealant canister and
place it in a highly visible
location.The maximum speed label
reminds you to drive cautiously
and not to exceed 55 mph
(90 km/h) until you have
the damaged tire inspected and
repaired.
{CAUTION
Storing the tire sealant and
compressor kit or other
equipment in the passenger
compartment of the vehicle
could cause injury. In a sudden
stop or collision, loose
equipment could strike
someone. Store the tire sealant
and compressor kit in its
original location.
16. Return the equipment to its
original storage location in
the trunk.
17. Immediately drive the vehicle
5 miles (8 km) to distribute the
sealant evenly in the tire.18. Stop at a safe location and
check the tire pressure, refer
to Steps 1 through 9 under
“Using the Tire Sealant
and Compressor Kit without
Sealant to Inate an
Underinated Tire” later in this
section.
If the tire pressure has fallen
more then 10 psi (68 kPa),
below the recommended
ination pressure, stop driving
the vehicle. The tire is too
severely damaged and the tire
sealant and compressor
cannot seal the tire. See
Roadside Assistance Program
on page 12-6if you need
assistance.
If the tire pressure has not
dropped more than 10 psi
(68 kPa) from the recommended
ination pressure, inate the tire
back up to the recommended
ination pressure.
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19. Wipe off any sealant from the
wheel, tire or vehicle.
20. Dispose of the used sealant
canister at a local dealer/retailer
or in accordance with local
state codes and practices.
After using the sealant canister,
replace it with a new canister
available from your
dealer/retailer.
This is a temporary repair. Take
the vehicle to your dealer/retailer
to have the tire repaired or
replaced as soon as possible.Using the Air Compressor
without Sealant to Inate an
Underinated Tire
To use the air compressor to inate
a tire with air only and not sealant:
A. Air Compressor Accessory Plug
B. Air Compressor
C. Sealant Canister
D. Sealant/Air Hose
E. Air-only Hose
F. Pressure Gage
G. On/Off SwitchDo a safety check before
proceeding. SeeIf a Tire Goes Flat
on page 9-62.
To use the air compressor to inate
a tire with air only and not sealant:
1. Lift the lever and pull the air-only
hose (E) from the bottom of
the kit.
2. Remove the tire valve stem cap
from the at tire by turning it
counterclockwise.
3. Push the air-only hose (E) onto
the tire valve stem and push
the lever down to secure in place.
4. Plug the air compressor
accessory plug (A) into an
accessory power outlet in the
vehicle. SeeAccessory Power
Outlet(s) on page 4-9for
more information.
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