service SATURN ASTRA 2009 Owners Manual

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.
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.
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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 9-52for
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 9-68.{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.
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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 9-49.
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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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
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.
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.
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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. It should benoted that 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.
{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, 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.
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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.
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 9-61for 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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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.
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 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 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.{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.
If a tire goes at, the next part
shows how to use the jacking
equipment to change a at tire
safely.
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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. SeeHazard
Warning Flashers on page 4-4.
{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.
(Continued)
CAUTION (Continued)
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).
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 the vehicle has a at tire (B),
use the following example as a
guide to assist you in the placement
of wheel blocks (A).
A. Wheel Block
B. Flat Tire
The following information explains
how to use the jack and change
a tire.
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Removing the Spare Tire
and Tools
The equipment you will need is
located in the rear storage area.
1. Open the liftgate. SeeLiftgate
on page 2-6.
2. Lift the oor cover to access the
spare tire and tools.3. Remove the foam pad. Turn the
retainer counterclockwise to
remove it.
4. Remove the spare tire by pulling
it up and out of the trunk.5. The jack and tools are stored
below the spare tire.
6. The tools you will be using
include the jack (A), wheel
wrench (B), screwdriver (C),
and jack handle (D).
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Removing the Flat Tire
and Installing the
Spare Tire
1. If your vehicle has wheel covers,
remove the cover.
Do not try to put a wheel cover
on your compact spare tire.
It will not t. Store the wheel
cover in the trunk until you have
the at tire repaired or replaced.
Notice:Wheel covers will not t
on your vehicle’s compact spare.
If you try to put a wheel cover on
the compact spare, the cover or
the spare could be damaged.
2. If your vehicle has wheel bolt
caps, remove the caps. Store
the caps with the wheel cover.3. Use the wheel wrench to loosen
all the wheel bolts. Do not
remove them yet.Notice:Make sure that the
jack lift head is in the correct
position or you may damage your
vehicle. The repairs would not
be covered by your warranty.
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