wheel SATURN ASTRA 2008 Service Manual

See your dealer/retailer for details
regarding winter tire availability
and proper tire selection. Also, see
Buying New Tires on page 9-54.
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 your original
equipment tires.
Winter tires with the same speed
rating as the 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.
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.
(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.Passenger (P-Metric) Tire
Example
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(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.
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 9-46.
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.
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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 9-50for
additional information.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 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.
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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, excluding the
spare tire. The TPMS sensors
monitor the air pressure in the
vehicle’s tires and transmit tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning
light located in the instrument
panel cluster.The low tire pressure warning light
comes on at each ignition cycle
until the tires are inated to
the correct ination pressure.
The low tire pressure warning light
may come on in cool weather
when the vehicle is rst started, and
then turn off as you start to drive.
This could be an early indicator that
the air pressure in the tire(s) are
getting low and need to be inated
to the proper pressure.
You must begin driving before the
TPMS system is operational.
TPMS sensors need to be installed
onto the full-size tire and wheel
assemblies, and the tires adjusted
to the manufacturers’ recommended
tire pressure amount.
A Tire and Load Information label is
attached to the vehicle, and shows
the size of the vehicle’s original
equipment tires and the correct
ination pressure for the tires when
they are cold. SeeLoading the
Vehicle on page 8-30, for anexample of the Tire and Load
Information label and its location on
the vehicle. Also seeInflation - Tire
Pressure on page 9-46.
The vehicle’s TPMS can warn you
about a low tire pressure condition
but it does not replace normal tire
maintenance. SeeTire Inspection
and Rotation on page 9-51andTires
on page 9-38.
Notice:Liquid tire sealants
could damage the Tire Pressure
Monitor System (TPMS) sensors.
Sensor damage caused by
using a tire sealant is not covered
by your warranty. Do not use
liquid tire sealants.
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 are automatically learned by
the TPMS. This occurs within a
few moments of driving the vehicle
over 19 mph (31 km/h).
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TPMS Malfunction Light
The TPMS will not function properly
if one or more of the TPMS
sensors are missing or inoperable.
When the system detects a
malfunction, the low tire warning
light ashes for about one minute
and then stays on for the remainder
of the ignition cycle. Some of the
conditions that can cause the
malfunction light to come on are:
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a TPMS
sensor. The TPMS malfunction
light and DIC message should go
off once you re-install the road tire
containing the TPMS sensor.
One or more TPMS sensors are
missing or damaged. The TPMS
malfunction light should go off
after the TPMS sensors are
installed and the vehicle is
driven for a few moments over
19 mph (31 km/h). See your
dealer/retailer for service.
Replacement tires or wheels do
not match the vehicle’s original
equipment tires or wheels. Tires
and wheels other than those
recommended for the vehicle
could prevent the TPMS from
functioning properly. SeeBuying
New Tires on page 9-54.
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 comes on and stays on.
Tire Inspection and
Rotation
Inspect tires regularly for signs of
wear or damage. Also inspect the
spare tire. For more information
on tire inspection, seeWhen It Is
Time for New Tires on page 9-53.
Rotating vehicle tires helps them
to wear evenly and keeps the
vehicle performing like it did
when tires were new.
Rotate the tires and check
wheel alignment approximately
every 5,000 to 8,000 miles
(8 000 to 13 000 km) or when
unusual tire wear is noted.
See “Scheduled Maintenance”
in the Index of the “Limited
Warranty, Maintenance
and Owner Assistance
Information” manual for more
information. Also check the
wheels for damage, seeWheel
Replacement on page 9-58
for more information.
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Use this pattern when rotating
the vehicle tires. Do not include
the compact spare tire in the
tire rotation.
{CAUTION
Rust or dirt on a wheel, or
on the parts to which it is
fastened, can make wheel
bolts become loose after
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 using a scraper
or wire brush.
Installing wheels with a good
metal-to-metal contact at
the mounting surfaces is
necessary to prevent wheel
bolts from becoming loose.To prevent corrosion or rust
build-up, lightly coat the wheel
hub center and the cone-shaped
surface of each wheel bolt
with wheel bearing grease,
after a wheel change.
SeeChanging a Flat Tire on
page 9-60for information
on installing the tire and wheel
assembly. Also see “Wheel
Bolt Torque” underCapacities
and Specifications on page 10-2.
Adjust the front and rear tires to
the recommended cold tire
ination pressure shown on the
Tire and Loading Information
label. SeeInflation - Tire
Pressure on page 9-46and
Loading the Vehicle on
page 8-30.
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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 an MS for mud and
snow. SeeTire Sidewall Labeling on
page 9-40for 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 9-51for
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 9-67.
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{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.
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 warninglevel you would get with TPC Spec
rated tires. SeeTire Pressure
Monitor System on page 9-48.
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, anti-lock
brakes, traction control, and
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 Saturn specic
wheel and tire systems
developed for your vehicle, and
have them properly installed by
a Saturn certied technician.
SeeBuying New Tires on page 9-54
andAccessories and Modifications
on page 9-3for additional
information.
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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 MotorVehicle 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.
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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 the wheel bolts keep coming
loose, the wheel and wheel bolts
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 or wheel bolts, replace
them only with new GM original
equipment parts. This way, you will
be sure to have the right wheel
and wheel bolts for the vehicle.
{CAUTION
Using the wrong replacement
wheels or wheel bolts on your
vehicle can be dangerous.
It could affect the braking and
handling of the vehicle, make
the tires lose air and make you
lose control of the vehicle. You
could have a collision in which
you or others could be injured.
Always use the correct wheel
and wheel bolts for replacement.
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