wheel SATURN SKY 2008 Service Manual

Brake Wear
Your vehicle has disc brakes. Front 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 5-99.
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 you apply the brakes, with or without the
vehicle moving, the brakes adjust for wear.
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Low-Prole Tires
If your vehicle has P245/45R18 size tires, they are
classied as low-prole 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.
Winter Tires
If your vehicle has P245/45R18 size tires, they are
classied as low-prole performance tires. These tires
are designed for very responsive driving on wet or
dry pavement. If you expect to drive on snow or
ice covered roads often, you may want to get wintertires for your vehicle. The low-prole performance tires
may not offer the traction you would like or the same
level of performance as winter tires on snow or ice
covered roads.
Winter tires, in general, are designed for increased
traction on snow and ice covered roads. With winter
tires, there may be decreased dry road traction,
increased road noise, and shorter tire tread life.
After switching to winter tires, be alert for changes in
vehicle handling and braking.
See your dealer/retailer for details regarding winter tire
availability and proper tire selection. Also, seeBuying
New Tires on page 5-66.
If you choose to use winter tires:
Use tires of the same brand and tread type on all
four wheel positions.
Use only radial ply tires of the same size, load range,
and speed rating as the original equipment tires.
Winter tires with the same speed rating as your original
equipment tires may not be available for H, V, W, Y,
and ZR speed rated tires. If you choose winter tires with
a lower speed rating, never exceed the tire’s maximum
speed capability.
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(G) Maximum Cold Ination Load Limit:Maximum load that can be carried and the
maximum pressure needed to support that load.
Tire Size
The following illustration shows an example of a
typical passenger (p-metric) 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.
(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.
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Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio
and sensor technology to check tire pressure levels.
The TPMS sensors monitor the air pressure in
your vehicle’s tires and transmit tire pressure readings
to a receiver located in the vehicle.
Each tire, including the spare (if provided), should be
checked monthly when cold and inated to the ination
pressure recommended by the vehicle manufacturer
on the vehicle placard or tire ination pressure label.
(If your vehicle has tires of a different size than the
size indicated on the vehicle placard or tire ination
pressure label, you should determine the proper
tire ination pressure for those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system (TPMS)
that illuminates a low tire pressure telltale when one
or more of your tires is signicantly under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires as
soon as possible, and inate them to the proper
pressure. Driving on a signicantly under-inated tire
causes the tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling
and stopping ability.Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-ination
has not reached the level to trigger illumination of
the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator
is combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will ash
for approximately one minute and then remain
continuously illuminated. This sequence will continue
upon subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low tire
pressure as intended. TPMS malfunctions may occur for
a variety of reasons, including the installation of
replacement or alternate tires or wheels on the vehicle
that prevent the TPMS from functioning properly.
Always check the TPMS malfunction telltale after
replacing one or more tires or wheels on your vehicle to
ensure that the replacement or alternate tires and
wheels allow the TPMS to continue to function properly.
SeeTire Pressure Monitor Operation on page 5-59,
for additional information.
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Federal Communications Commission
(FCC) and Industry and Science
Canada
The Tire Pressure Monitor System (TPMS) operates on
a radio frequency and complies with Part 15 of the
FCC Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
The Tire Pressure Monitor System (TPMS) operates on
a radio frequency and complies with RSS-210 of
Industry and Science Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Tire Pressure Monitor Operation
The Tire Pressure Monitor System (TPMS) is designed
to warn the driver when a low tire pressure condition
exists. TPMS sensors are mounted onto each tire
and wheel assembly. The TPMS sensors monitor the air
pressure in the vehicle’s tires and transmits the tire
pressure readings to a receiver located in the vehicle.
When a low tire pressure
condition is detected, the
TPMS turns on the low tire
pressure warning light
located on the instrument
panel cluster.
At the same time a message to check the pressure in a
specic tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and the
DIC warning message come on at each ignition cycle
until the tires are inated to the correct ination pressure.
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Replacement tires or wheels do not match your
vehicle’s original equipment tires or wheels.
Tires and wheels other than those recommended
for your vehicle could prevent the TPMS from
functioning properly. SeeBuying New Tires on
page 5-66.
Operating electronic devices or being near
facilities using radio wave frequencies similar
to the TPMS could cause the TPMS sensors to
malfunction.
If the TPMS is not functioning it cannot detect or
signal a low tire condition. See your 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 you replace one or more of the TPMS sensors
or rotate the vehicle’s tires, 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.
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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 seconds to start the TPMS
learn mode. The horn sounds twice indicating the
TPMS receiver is ready and in learn mode.
4. Start with the driver side front tire. The driver side
front turn signal 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 chirp, can take up to
30 seconds to sound. It chirps one time and then
all the turn signals ash one time to conrm the
sensor identication code has been matched to
the tire/wheel position.
6. The passenger side front turn signal comes on to
indicate that corner sensor is ready to be learned.
Proceed to the passenger side front tire and
repeat the procedure in Step 5.7. The passenger side rear turn signal comes on to
indicate that corner sensor is ready to be learned.
Proceed to the passenger side rear tire and
repeat the procedure in Step 5.
8. The driver side rear turn signal comes on to
indicate that corner sensor is ready to be learned.
Proceed to the driver side rear tire, and repeat
the procedure in Step 5.
9. After hearing the single horn chirp for the driver
side rear tire, two additional horn chirps sound to
indicate the tire learning process is done.
Turn the ignition switch to LOCK/OFF.
If no tires are learned after entering the TPMS
learn mode, or if communication with the receiver
stops, or if the time limit has expired, turn the
ignition switch to LOCK/OFF and start over
beginning with Step 2.
10. Set all four tires to the recommended air pressure
level as indicated on the Tire and Loading
Information label.
11. Put the valve caps back on the valve stems.
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Tire Inspection and Rotation
We recommend that you regularly inspect your
vehicle’s tires for signs of wear or damage.
SeeWhen It Is Time for New Tires on page 5-65
for more information.
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km). SeeScheduled Maintenance
on page 6-4.
The purpose of a regular tire rotation is to achieve
a uniform wear for all tires on the vehicle. This
will ensure that your vehicle continues to perform
most like it did when the tires were new.
Any time you notice unusual wear, rotate the tires
as soon as possible and check wheel alignment.
Also check for damaged tires or wheels. See
When It Is Time for New Tires on page 5-65and
Wheel Replacement on page 5-70.When rotating Goodyear Eagle RSA P245/45R18
non-directional tires, always use the correct
rotation pattern shown here.
Non-Directional Tires
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If your vehicle has Goodyear Eagle F1-GS1
P245/45R18 size tires, they are directional tires
and must roll in a certain direction for the
best overall performance. The direction is shown
by an arrow on the tire sidewall. Because these
tires are directional, they should be rotated as
shown here. These tires should only be moved
from front to rear and rear to front on the same
side of the vehicle.After the tires have been rotated, adjust the
front and rear ination pressures as shown
on the Tire and Loading Information label.
SeeInflation - Tire Pressure on page 5-56
andLoading Your Vehicle on page 4-23.
Reset the Tire Pressure monitor System.
SeeTire Pressure Monitor Operation on page 5-59.
Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications on page 5-99.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel
could come off and cause a crash. When
you change a wheel, remove any rust or
dirt from places where the wheel attaches
to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this;
but be sure to use a scraper or wire brush
later, if you need to, to get all the rust or
dirt off.Directional Tires
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Buying New Tires
GM has developed and matched specic tires for your
vehicle. The original equipment tires installed on
your vehicle, when it was new, were designed to meet
General Motors Tire Performance Criteria Specication
(TPC spec) system rating. If you need replacement
tires, GM strongly recommends that you get tires with
the same TPC Spec rating. This way, your vehicle
will continue to have tires that are designed to give the
same performance and vehicle safety, during normal
use, as the original tires.
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 a MS, for mud
and snow. SeeTire Sidewall Labeling on page 5-52
for 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 5-63
for 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 your vehicle. Be sure to use the
correct size, brand, and type of tires on your
vehicle’s wheels.
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