tire size SATURN ASTRA 2009 Owners Manual

{CAUTION
It can be dangerous to get out of
the vehicle if the automatic
transmission shift lever is not fully
in P (Park) with the parking brake
rmly set. The vehicle can roll. Do
not leave the vehicle when the
engine is running unless you have
to. If you have left the engine
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when you are on
fairly level ground, always set the
parking brake and move the shift
lever to P (Park).
Follow the proper steps to be sure
the vehicle will not move. See
Shifting Into Park on page 8-11.
Driving Your Vehicle
Driving for Better
Fuel Economy
Driving habits can affect fuel
mileage. Here are some driving tips
to get the best fuel economy
possible.
Avoid fast starts and accelerate
smoothly.
Brake gradually and avoid abrupt
stops.
Avoid idling the engine for long
periods of time.
When road and weather
conditions are appropriate, use
cruise control, if equipped.
Always follow posted speed limits
or drive more slowly when
conditions require.
Keep vehicle tires properly
inated.
Combine several trips into a
single trip.
Replace the vehicle’s tires with
the same TPC Spec number
molded into the tire’s sidewall
near the size.
Follow recommended scheduled
maintenance.
Driving and Operating 8-15
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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 9-40
andInflation - Tire Pressure on
page 9-47.
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.Steps for Determining Correct
Load Limit
1.Locate the statement “The
combined weight of occupants
and cargo should never
exceed XXX kg or XXX lbs”
on your vehicle placard.
2.Determine the combined
weight of the driver and
passengers that will be riding
in your vehicle.
3.Subtract the combined weight
of the driver and passengers
from XXX kg or XXX lbs.
4.The resulting gure equals
the available amount of cargo
and luggage load capacity.
For example, if the “XXX”
amount equals 1400 lbs
and there will be ve 150 lb
passengers in your vehicle,
the amount of available cargo
and luggage load capacity
is 650 lbs (1400−750
(5 x 150) = 650 lbs).
5.Determine the combined
weight of luggage and
cargo being loaded on the
vehicle. That weight may not
safely exceed the available
cargo and luggage load
capacity calculated in Step 4.
6.If your vehicle will be towing a
trailer, the load from your
trailer will be transferred to
your vehicle. Consult this
manual to determine how this
reduces the available cargo
and luggage load capacity of
your vehicle.
The vehicle is neither designed
nor intended to tow a trailer.
Driving and Operating 8-31
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When It Is Time for
New Tires.......................9-54
Buying New Tires.............9-54
Different Size Tires and
Wheels............................9-56
Uniform Tire Quality
Grading...........................9-57
Wheel Alignment and
Tire Balance....................9-58
Wheel Replacement..........9-59
Tire Chains.......................9-60
Tire ChangingIf a Tire Goes Flat............9-60
Changing a Flat Tire.........9-61
Removing the Spare Tire
and Tools........................9-62
Removing the Flat Tire
and Installing the
Spare Tire
.......................9-63
Storing a Flat or Spare
Tire and Tools.................9-66
Compact Spare Tire..........9-68
Jump Starting
Jump Starting...................9-69
Towing
Towing Your Vehicle.........9-73
Recreational Vehicle
Towing............................9-73
Towing a Trailer................9-73
Appearance Care
Interior Cleaning................9-73
Exterior Cleaning..............9-76
Sheet Metal Damage........9-79
Finish Damage..................9-79
Underbody Maintenance. . . .9-80
Chemical Paint Spotting. . . .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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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 inationpressure 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.
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.
Vehicle Service and Care 9-41
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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.
(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 9-57.
(G) Maximum Cold Ination
Load Limit
:Maximum load
that can be carried and
the maximum pressure needed
to support that load.
Passenger (P-Metric) Tire
Example
9-42 Vehicle Service and Care
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(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 9-68andIf 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.
(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 9-47.(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.
Compact Spare Tire Example
Vehicle Service and Care 9-43
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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.
(D) Construction Code
:A letter
code is used to indicate the
type of ply construction in the
tire. The letter R means radial
ply construction; the letter D
means diagonal or bias ply
construction; and the letter B
means belted-bias ply
construction.
(E) Rim Diameter
:Diameter of
the wheel in inches.
(F) Service Description
:These characters represent the
load index and speed rating
of the tire. The load index
represents the load carry
capacity a tire is certied to
carry. The speed rating is the
maximum speed a tire is certied
to carry a load.
Tire Terminology and
Denitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch
of the tire. Air pressure is
expressed in pounds per square
inch (psi) or kilopascal (kPa).
Accessory Weight
:This means
the combined weight of optional
accessories. Some examples
of optional accessories are,
automatic transmission, power
steering, power brakes, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire’s height to its width.
Belt
:A rubber coated layer of
cords that is located between the
plies and the tread. Cords may
be made from steel or other
reinforcing materials.
9-44 Vehicle Service and Care
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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.
Ination - Tire Pressure
Tires need the correct amount of
air pressure to operate effectively.
Notice:Do not let anyone tell
you that under-ination or
over-ination is all right. It is
not. If your tires do not have
enough air (under-ination),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air
(over-ination), you can get
the following:
Unusual wear
Poor handling
Rough ride
Needless damage from
road hazardsA vehicle specic Tire and
Loading Information label is
attached to your vehicle.
This label shows your vehicle’s
original equipment tires and
the correct ination pressures for
your tires when they are cold.
The recommended cold tire
ination pressure, shown on the
label, is the minimum amount
of air pressure needed to
support your vehicle’s maximum
load carrying capacity.
For additional information
regarding how much weight your
vehicle can carry, and an
example of the Tire and Loading
Information label, seeLoading
the Vehicle on page 8-30.
How you load your vehicle
affects vehicle handling and ride
comfort. Never load your
vehicle with more weight than it
was designed to carry.
Vehicle Service and Care 9-47
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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).
When high-speed driving ends,
return the tire pressure to the
recommended cold ination
pressure shown on the Tire and
Loading Information label.SeeLoading the Vehicle on
page 8-30. Tire pressure should be
checked and correctly set when
the tires are cold. SeeInflation - Tire
Pressure on page 9-47.
Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor
the air pressure in your vehicle’s tires
and transmit tire pressure readings to
a receiver located in the vehicle.
Each tire, including the spare
(if provided), should be checked
monthly when cold and inated to
the ination pressure recommended
by the vehicle manufacturer on
the vehicle placard or tire ination
pressure label. (If your vehicle
has tires of a different size than the
size indicated on the vehicle
placard or tire ination pressure
label, you should determine the
proper tire ination pressure
for those tires.)As an added safety feature, your
vehicle has been equipped with
a tire pressure monitoring system
(TPMS) that illuminates a low
tire pressure telltale when one or
more of your tires is signicantly
under-inated.
Accordingly, when the low tire
pressure telltale illuminates, you
should stop and check your tires as
soon as possible, and inate them to
the proper pressure. Driving on a
signicantly under-inated tire
causes the tire to overheat and can
lead to tire failure. Under-ination
also reduces fuel efficiency and
tire tread life, and may affect the
vehicle’s handling and stopping
ability.
Please note that the TPMS is
not a substitute for proper tire
maintenance, and it is the driver’s
responsibility to maintain correct tire
pressure, even if under-ination
has not reached the level to trigger
illumination of the TPMS low tire
pressure telltale.
Vehicle Service and Care 9-49
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Tire Pressure Monitor
Operation
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS is designed to warn
the driver when a low tire pressure
condition exists. TPMS sensors
are mounted onto each tire and
wheel assembly, excluding the
spare tire. The TPMS sensors
monitor the air pressure in the
vehicle’s tires and transmit tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning
light located in the instrument
panel cluster.The low tire pressure warning light
comes on at each ignition cycle
until the tires are inated to
the correct ination pressure.
The low tire pressure warning light
may come on in cool weather
when the vehicle is rst started, and
then turn off as you start to drive.
This could be an early indicator that
the air pressure in the tire(s) are
getting low and need to be inated
to the proper pressure.
You must begin driving before the
TPMS system is operational.
TPMS sensors need to be installed
onto the full-size tire and wheel
assemblies, and the tires adjusted
to the manufacturers’ recommended
tire pressure amount.
A Tire and Load Information label is
attached to the vehicle, and
shows the size of the vehicle’s
original equipment tires and
the correct ination pressure for the
tires when they are cold. See
Loading the Vehicle on page 8-30,
for an example of the Tire andLoad Information label and its
location on the vehicle. Also see
Inflation - Tire Pressure on
page 9-47.
The vehicle’s TPMS can warn you
about a low tire pressure condition
but it does not replace normal
tire maintenance. SeeTire
Inspection and Rotation on
page 9-52andTires on page 9-40.
Notice:Liquid tire sealants
could damage the Tire Pressure
Monitor System (TPMS) sensors.
Sensor damage caused by
using a tire sealant is not covered
by your warranty. Do not use
liquid tire sealants.
Each TPMS sensor has a unique
identication code. Any time
you replace one or more of the
TPMS sensors or rotate the
vehicle’s tires, the identication
codes are automatically learned by
the TPMS. This occurs within a
few moments of driving the vehicle
over 19 mph (31 km/h).
Vehicle Service and Care 9-51
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