SATURN ASTRA 2008 Owners Manual

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.
Vehicle Service and Care 9-51
ProCarManuals.com

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.
9-52 Vehicle Service and Care
ProCarManuals.com

When It Is Time for
New Tires
Various factors, such as
maintenance, temperatures,
driving speeds, vehicle loading,
and road conditions inuence
when you need new tires.
One way to tell when it is time for
new tires is to check the treadwear
indicators, which will appear when
the tires have only 1/16 inch
(1.6 mm) or less of tread remaining.You need new tires if any of the
following statements are true:You can see the indicators at
three or more places around
the tire.
You can see cord or fabric
showing through the tire’s rubber.
The tread or sidewall is cracked,
cut, or snagged deep enough to
show cord or fabric.
The tire has a bump, bulge,
or split.
The tire has a puncture, cut, or
other damage that cannot be
repaired well because of the size
or location of the damage.The rubber in tires degrades over
time, even if they are not being
used. This is also true for the
spare tire, if the vehicle has one.
Multiple conditions affect how
fast this aging takes place, including
temperatures, loading conditions,
and ination pressure maintenance.
With proper care and maintenance
tires typically wear out before
they degrade due to age. If you are
unsure about the need to replace
the tires as they get older, consult
the tire manufacturer for more
information.
Vehicle Service and Care 9-53
ProCarManuals.com

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.
9-54 Vehicle Service and Care
ProCarManuals.com

{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.
Vehicle Service and Care 9-55
ProCarManuals.com

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 grades are moldedon 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.
9-56 Vehicle Service and Care
ProCarManuals.com

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.
Vehicle Service and Care 9-57
ProCarManuals.com

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.
9-58 Vehicle Service and Care
ProCarManuals.com

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 9-60for 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.
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 9-59
ProCarManuals.com

Tire Changing
If a Tire Goes Flat
It is unusual for a tire to blowout
while you are driving, especially if
you maintain your vehicle’s tires
properly. 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 creates
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 theway 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.
{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.
If a tire goes at, the next part
shows how to use the jacking
equipment to change a at tire
safely.
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)
9-60 Vehicle Service and Care
ProCarManuals.com