2008 SATURN ASTRA tire size

{CAUTION
Do not load the vehicle any
heavier than the Gross
Vehicle Weight Rating
(GVWR), or either the
maximum front or rear
Gross Axle Weight Rating
(GAWR). If you do, parts on
the vehicle can break, and it
can change the way your
vehicle handles. These
could cause you to lose
control and crash. Also,
overloading can shorten
the life of the vehicle.Tire and Loading Information
Label
A vehicle specic Tire and
Loading Information label
is attached to the vehicle’s
center pillar (B-pillar). With the
driver’s door open, you will
nd the label attached below
the door lock post. The Tireand Loading Information label
shows the number of occupant
seating positions (A), and
the maximum vehicle capacity
weight (B) in kilograms and
pounds.
The Tire and Loading
Information label also shows the
tire size of the original equipment
tires (C) and the recommended
cold tire ination pressures (D).
For more information on tires and
ination seeTires on page 9-38
andInflation - Tire Pressure on
page 9-46.
There is also important loading
information on the Certication
label. It tells you the Gross
Vehicle Weight Rating (GVWR)
and the Gross Axle Weight
Rating (GAWR) for the front and
rear axle; see “Certication
Label” later in this section.
Label Example
Driving and Operating 8-31
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Buying New Tires.............9-54
Different Size Tires
and Wheels.....................9-55
Uniform Tire Quality
Grading...........................9-56
Wheel Alignment and
Tire Balance....................9-58
Wheel Replacement..........9-58
Tire Chains.......................9-59
Tire Changing
If a Tire Goes Flat............9-60
Changing a Flat Tire.........9-60
Removing the Spare
Tire and Tools.................9-61
Removing the Flat Tire
and Installing the
Spare Tire
.......................9-62
Storing a Flat or Spare
Tire and Tools.................9-66
Compact Spare Tire..........9-67
Jump Starting
Jump Starting...................9-68
Towing
Towing Your Vehicle.........9-72
Recreational Vehicle
Towing............................9-72
Towing a Trailer................9-72
Appearance Care
Interior Cleaning................9-72
Exterior Cleaning..............9-75
Sheet Metal Damage........9-78
Finish Damage..................9-79
Underbody Maintenance. . . .9-79
Chemical Paint Spotting. . . .9-79
Vehicle Care/Appearance
Materials.........................9-80
Service
For service and parts needs,
visit your dealer/retailer. You will
receive genuine Saturn parts
and Saturn-trained and supported
service people.
Genuine Saturn parts have one of
these marks.
9-2 Vehicle Service and Care
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CAUTION (Continued)
Worn, old tires can cause
accidents. If your tread
is badly worn, or if your
tires have been damaged,
replace them.
SeeHigh-Speed Operation
on page 9-47for ination
pressure adjustment for
high speed driving.
Low-Prole Tires
If the vehicle has 225/40ZR18
or 215/45R18 size tires, they
are classied as low-prole
performance tires. These tires
are designed for very responsive
driving on wet or dry pavement.
You may also notice more
road noise with low-prole
performance tires and that they
tend to wear faster.
Notice:If the vehicle has
low-prole tires, they are
more susceptible to damage
from road hazards or curb
impact than standard prole
tires. Tire and/or wheel
assembly damage can occur
when coming into contact with
road hazards like, potholes,
or sharp edged objects,
or when sliding into a curb.
The vehicle warranty does not
cover this type of damage.
Keep tires set to the correct
ination pressure and,
when possible avoid contact
with curbs, potholes, and
other road hazards.Winter Tires
If the vehicle has 225/40ZR18 or
215/45R18 size tires, they are
classied as low-prole performance
tires. These tires are designed for
very responsive driving on wet or dry
pavement. If you expect to drive
on snow or ice covered roads often,
you may want to get winter tires
for your vehicle. All season tires
provide good overall performance on
most surfaces but they may not
offer the traction you would like or
the same level of performance
as winter tires on snow or ice
covered roads.
Winter tires, in general, are
designed for increased traction on
snow and ice covered roads.
With winter tires, there may be
decreased dry road traction,
increased road noise, and shorter
tire tread life. After switching to
winter tires, be alert for changes in
vehicle handling and braking.
Vehicle Service and Care 9-39
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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
9-40 Vehicle Service and Care
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(D) Tire Identication Number
(TIN):The letters and numbers
following DOT (Department
of Transportation) code is the
Tire Identication Number (TIN).
The TIN shows the manufacturer
and plant code, tire size, and
date the tire was manufactured.
The TIN is molded onto both
sides of the tire, although only
one side may have the date
of manufacture.
(E) Tire Ply Material
:The type
of cord and number of plies in the
sidewall and under the tread.
(F) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required to
grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more information
seeUniform Tire Quality
Grading on page 9-56.(G) Maximum Cold Ination
Load Limit
:Maximum load
that can be carried and the
maximum pressure needed to
support that load.
(A) Tire Ply Material
:The type
of cord and number of plies in the
sidewall and under the tread.(B) Temporary Use Only
:The compact spare tire or
temporary use tire has a tread
life of approximately 3,000 miles
(5 000 km) and should not be
driven at speeds over 50 mph
(80 km/h). The compact
spare tire is for emergency use
when a regular road tire has
lost air and gone at. If your
vehicle has a compact spare tire.
SeeCompact Spare Tire on
page 9-67andIf a Tire
Goes Flat on page 9-60.
(C) Tire Identication
Number (TIN)
:The letters and
numbers following the DOT
(Department of Transportation)
code is the Tire Identication
Number (TIN). The TIN shows
the manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
Compact Spare Tire Example
Vehicle Service and Care 9-41
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(D) Maximum Cold Ination
Load Limit:Maximum load that
can be carried and the maximum
pressure needed to support
that load.
(E) Tire Ination
:The
temporary use tire or compact
spare tire should be inated
to 60 psi (420 kPa). For more
information on tire pressure
and ination seeInflation - Tire
Pressure on page 9-46.
(F) Tire Size
:A combination of
letters and numbers dene a
tire’s width, height, aspect ratio,
construction type, and service
description. The letter T as
the rst character in the tire size
means the tire is for temporary
use only.(G) 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.
Tire Size
The following illustration shows
an example of a typical
passenger vehicle tire size.(A) Passenger (P-Metric) Tire
:The United States version of a
metric tire sizing system.
The letter P as the rst
character in the tire size
means a passenger vehicle tire
engineered to standards set by
the U.S. Tire and Rim
Association.
(B) Tire Width
:The three-digit
number indicates the tire section
width in millimeters from sidewall
to sidewall.
(C) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item C of the illustration, it would
mean that the tire’s sidewall is
60 percent as high as it is wide.
9-42 Vehicle Service and Care
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Passenger (P-Metric) Tire:A tire used on passenger cars
and some light duty trucks
and multipurpose vehicles.
Recommended Ination
Pressure
:Vehicle
manufacturer’s recommended
tire ination pressure as shown
on the tire placard. See
Inflation - Tire Pressure on
page 9-46andLoading
the Vehicle on page 8-30.
Radial Ply Tire
:A pneumatic
tire in which the ply cords that
extend to the beads are laid
at 90 degrees to the centerline
of the tread.
Rim
:A metal support for a tire
and upon which the tire beads
are seated.
Sidewall
:The portion of a tire
between the tread and the bead.
Speed Rating
:An alphanumeric
code assigned to a tire indicating
the maximum speed at which a
tire can operate.Traction
:The friction between
the tire and the road surface.
The amount of grip provided.
Tread
:The portion of a tire that
comes into contact with the road.
Treadwear Indicators
:Narrow
bands, sometimes called wear
bars, that show across the tread
of a tire when only 1/16 inch
(1.6 mm) of tread remains.
SeeWhen It Is Time for New
Tires on page 9-53.
UTQGS (Uniform Tire Quality
Grading Standards)
:A tire
information system that provides
consumers with ratings for a
tire’s traction, temperature,
and treadwear. Ratings are
determined by tire manufacturers
using government testing
procedures. The ratings are
molded into the sidewall of the
tire. SeeUniform Tire Quality
Grading on page 9-56.Vehicle Capacity Weight
:The number of designated
seating positions multiplied
by 150 lbs (68 kg) plus the
rated cargo load. SeeLoading
the Vehicle on page 8-30.
Vehicle Maximum Load on
the Tire
:Load on an individual
tire due to curb weight,
accessory weight, occupant
weight, and cargo weight.
Vehicle Placard
:A label
permanently attached to a
vehicle showing the vehicle’s
capacity weight and the original
equipment tire size and
recommended ination pressure.
See “Tire and Loading
Information Label” under
Loading the Vehicle on
page 8-30.
Vehicle Service and Care 9-45
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Remove the valve cap from the
tire valve stem. Press the
tire gage rmly onto the valve to
get a pressure measurement.
If the cold tire ination pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the ination pressure is low,
add air until you reach the
recommended amount.
If you overll the tire, release air
by pushing on the metal stem
in the center of the tire valve.
Re-check the tire pressure with
the tire gage.
Be sure to put the valve caps
back on the valve stems.
They help prevent leaks by
keeping out dirt and moisture.High-Speed Operation
{CAUTION
Driving at high speeds, 100 mph
(160 km/h) or higher, puts an
additional strain on tires.
Sustained high-speed driving
causes excessive heat build up
and can cause sudden tire
failure. You could have a crash
and you or others could be
killed. Some high-speed rated
tires require ination pressure
adjustment for high speed
operation. When speed limits
and road conditions are such
that a vehicle can be driven at
high speeds, make sure the
tires are rated for high speed
operation, in excellent
condition, and set to the correct
cold tire ination pressure for
the vehicle load.If the vehicle has P205/55R16 size
tires, additional air pressure is
required when driving the vehicle at
speeds of 99 mph (158 km/h) or
higher. Set the cold tire ination
pressure to the maximum ination
pressure shown on the tire sidewall,
or 32 psi (220 kPa), whichever is
lower. See the example following.
Example:
The maximum load and ination
pressure is molded on the tire’s
sidewall, in small letters, near the
rim ange. It reads something
like this: Maximum load 710 kg
(1565 lbs) 350 kPa (51 psi) Max.
Press.
For this example, the cold tire
ination pressure for high-speed
driving should be set at 32 psi
(220 kPa).
Vehicle Service and Care 9-47
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