tire size SATURN ASTRA 2008 User Guide

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
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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.
9-54 Vehicle Service and Care
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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.
Vehicle Service and Care 9-55
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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
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4. Put the load oor back in place.
The compact spare tire is for
temporary use only. Replace the
compact spare with a full-size tire
as soon as possible.
Compact Spare Tire
Although the compact spare tire
was fully inated when the vehicle
was new, it can lose air after
a time. Check the ination
pressure regularly. It should be
60 psi (420 kPa).
After installing the compact spare
on the vehicle, stop as soon
as possible and make sure the
spare tire is correctly inated.
The compact spare is made to
perform well at speeds up to
50 mph (80 km/h) for distances
up to 3,000 miles (5 000 km), so you
can nish your trip and have the
full-size tire repaired or replaced at
your convenience. Of course, it
is best to replace the spare with a
full-size tire as soon as possible.
The spare tire will last longer and
be in good shape in case it is
needed again.Notice:When the compact
spare is installed, do not take
your vehicle through an
automatic car wash with guide
rails. The compact spare can get
caught on the rails. That can
damage the tire and wheel, and
maybe other parts of your vehicle.
Do not use the compact spare on
other vehicles.
And do not mix the compact spare
tire or wheel with other wheels
or tires. They will not t. Keep the
spare tire and its wheel together.
Notice:Tire chains will not
t your compact spare. Using
them can damage your vehicle
and can damage the chains
too. Do not use tire chains on
your compact spare.
Vehicle Service and Care 9-67
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T
Tachometer.........................4-13
Taillamps....................9-29, 9-30
Theft-Deterrent, Radio...........6-24
Theft-Deterrent Systems......... 2-7
Content Theft-Deterrent....... 2-9
Immobilizer........................ 2-7
Immobilizer Operation......... 2-8
Tilt Wheel............................. 4-4
Tire
Pressure Light..................4-19
Tires..................................9-38
Buying New Tires.............9-54
Chains............................9-59
Changing a Flat Tire.........9-60
Compact Spare Tire..........9-67
Different Size...................9-55
High-Speed Operation.......9-47
If a Tire Goes Flat............9-60
Ination - Tire Pressure.....9-46Tires (cont.)
Inspection and Rotation.....9-51
Installing the Spare Tire.....9-62
Pressure Monitor
Operation.....................9-50
Pressure Monitor
System........................9-48
Removing the Flat Tire......9-62
Removing the Spare
Tire and Tools...............9-61
Storing a Flat or Spare
Tire and Tools...............9-66
Tire Sidewall Labeling.......9-40
Tire Terminology and
Denitions....................9-43
Uniform Tire Quality
Grading.......................9-56
Wheel Alignment and
Tire Balance.................9-58
Wheel Replacement..........9-58Tires (cont.)
When It Is Time for
New Tires....................9-53
Winter Tires.....................
9-39
Towing
Recreational Vehicle..........9-72
Towing a Trailer................9-72
Your Vehicle.....................9-72
Traction
Stabilitrak
®System...........8-19
Transmission
Fluid, Automatic................9-12
Fluid, Manual...................9-12
Transmission Operation,
Automatic.......................... 8-5
Transmission Operation,
Manual............................. 8-9
Trip Odometers....................4-13
Turn and Lane-Change
Signals............................. 4-8
Turn Signal/Multifunction
Lever................................ 4-4
INDEX i-9
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U
Uniform Tire Quality
Grading...........................9-56
Using this Manual..................... ii
V
Vehicle
Control............................8-17
Loading...........................8-30
Parking Your....................8-13
Running While Parked.......8-14
Service Soon Light...........4-24
Symbols.............................. iii
Vehicle Data Recording
and Privacy....................11-15
Vehicle Identication
Number (VIN)...................10-1
Service Parts
Identication Label.........10-1
Ventilation Adjustment............. 7-4
Visors.................................2-11
W
Warning Lights, Gages
and Indicators..................4-11
Warnings
DIC Warnings and
Messages....................4-37
Hazard Warning Flashers.... 4-4
Wheels
Alignment and Tire
Balance.......................9-58
Different Size...................9-55
Replacement....................9-58
Where to Put the Restraint....1-43
Windows.............................2-10
Power .............................2-10
Windshield
Washer...........................4-10
Washer Fluid....................9-20
Wiper Blade
Replacement................9-21Windshield (cont.)
Wiper Fuses....................9-34
Wipers.............................. 4-9
Windshield, Rear Washer/
Wiper..............................4-10
Winter Driving......................8-27
Winter Driving Mode Light.....4-23
Winter Tires........................9-39
i-10 INDEX
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