width SATURN ASTRA 2008 Owners Manual

{CAUTION
You can be seriously injured by
a twisted belt. In a crash, you
would not have the full width
of the belt to spread impact
forces. If a belt is twisted,
make it straight so it can work
properly, or ask your dealer/
retailer to x it.
Lap-Shoulder Belt
All seating positions in the vehicle
have a lap-shoulder belt.
Here is how to wear a lap-shoulder
belt properly.
1. Adjust the seat so you can sit up
straight. To see how, see “Seats”
in the Index.2. Pick up the latch plate and pull
the belt across you. Do not let
it get twisted.
The lap-shoulder belt may lock if
you pull the belt across you very
quickly. If this happens, let the
belt go back slightly to unlock it.
Then pull the belt across you
more slowly.
If you ever pull the shoulder
portion of a passenger belt out
all the way, you may engage the
child restraint locking feature.
If this happens, just let the belt go
back all the way and start again.3. Push the latch plate into the
buckle until it clicks.
Pull up on the latch plate to
make sure it is secure. If the belt
is not long enough, seeSafety
Belt Extender on page 1-22.
Make sure the release button on
the buckle is positioned so you
would be able to unbuckle the
safety belt quickly if necessary.
Seats and Restraints 1-17
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3. Record the distance from the
ground to the aim dot on the
low-beam headlamp.
4. At a wall, measure from the
ground upward (A) to the
recorded distance from Step 3
and mark it.
5. Draw or tape a horizontal line (B)
on the wall the width of the
vehicle at the height of the
mark in Step 4.Notice:Do not cover a headlamp
to improve beam cut-off when
aiming. Covering a headlamp may
cause excessive heat build-up
which may cause damage to the
headlamp.
6. Turn on the low-beam headlamps
and place a piece of cardboard
or equivalent in front of the
headlamp not being adjusted.
Do not place it directly on
the headlamp. This allows only
the beam of light from the
headlamp being adjusted to
be seen on the at surface.7. Locate the vertical headlamp
aiming screws, which are under
the hood near each headlamp
assembly.
The adjustment screw can be
turned with a 6 mm socket
wrench.
8. Turn the vertical aiming screw
until the headlamp beam is aimed
to the horizontal tape line. Turn it
clockwise or counterclockwise
to raise or lower the angle of
the beam.
Vehicle Service and Care 9-27
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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) 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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(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 range and speed rating
of the tire. The load index
represents the load carry
capacity a tire is certied to
carry. The load index can range
from 1 to 279. The speed
rating is the maximum speed a
tire is certied to carry a load.
Speed ratings range from A to Z.
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.Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a
tire, measured in pounds
per square inch (psi) or
kilopascals (kPa) before a tire
has built up heat from driving.
SeeInflation - Tire Pressure on
page 9-46.
Curb Weight
:The weight of a
motor vehicle with standard
and optional equipment including
the maximum capacity of fuel,
oil, and coolant, but without
passengers and cargo.
Vehicle Service and Care 9-43
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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.
9-56 Vehicle Service and Care
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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.
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.
9-58 Vehicle Service and Care
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