2008 SATURN ASTRA tire type

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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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.
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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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