2009 SATURN ASTRA tire type

Passing
Passing another vehicle on a
two-lane road can be dangerous.
To reduce the risk of danger
while passing:
Look down the road, to the sides,
and to crossroads for situations
that might affect a successful
pass. If in doubt, wait.
Watch for traffic signs, pavement
markings, and lines that could
indicate a turn or an intersection.
Never cross a solid or
double-solid line on your side of
the lane.
Do not get too close to the vehicle
you want to pass. Doing so can
reduce your visibility.
Wait your turn to pass a slow
vehicle.
When you are being passed, ease
to the right.
Loss of Control
Let us review what driving experts
say about what happens when
the three control systems — brakes,
steering, and acceleration — do
not have enough friction where the
tires meet the road to do what
the driver has asked.
In any emergency, do not give up.
Keep trying to steer and constantly
seek an escape route or area of
less danger.
Skidding
In a skid, a driver can lose control of
the vehicle. Defensive drivers avoid
most skids by taking reasonable care
suited to existing conditions, and by
not overdriving those conditions.
But skids are always possible.The three types of skids correspond
to the vehicle’s three control
systems. In the braking skid, the
wheels are not rolling. In the steering
or cornering skid, too much speed
or steering in a curve causes tires
to slip and lose cornering force.
And in the acceleration skid, too
much throttle causes the driving
wheels to spin.
If the vehicle starts to slide, ease
your foot off the accelerator pedal
and quickly steer the way you want
the vehicle to go. If you start steering
quickly enough, the vehicle may
straighten out. Always be ready for a
second skid if it occurs.
Of course, traction is reduced when
water, snow, ice, gravel, or other
material is on the road. For safety,
slow down and adjust your driving to
these conditions. It is important to
slow down on slippery surfaces
because stopping distance is longer
and vehicle control more limited.
8-22 Driving and Operating
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Driving in Rain and on
Wet Roads
Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep-standing or owing water.
{CAUTION
Wet brakes can cause crashes.
They might not work as well in a
quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
(Continued)
CAUTION (Continued)
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.
Flowing or rushing water creates
strong forces. Driving through
owing water could cause your
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through owing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under your vehicle’s
tires so they actually ride on
the water. This can happen if the
road is wet enough and you
are going fast enough. When your
vehicle is hydroplaning, it has little or
no contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is
to slow down when the road is wet.
8-24 Driving and Operating
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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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When to Check
Check your tires once a month
or more. Do not forget to
check the compact spare tire,
it should be at 60 psi (420 kPa).
For additional information
regarding the compact spare
tire, seeCompact Spare Tire
on page 9-68.
How to Check
Use a good quality pocket-type
gage to check tire pressure.
You cannot tell if your tires are
properly inated simply by
looking at them. Radial tires
may look properly inated even
when they are under-inated.
Check the tire’s ination
pressure when the tires are
cold. Cold means your vehicle
has been sitting for at least
three hours or driven no more
than 1 mile (1.6 km).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.
9-48 Vehicle Service and Care
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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 9-42for 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 9-52for
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 9-68.{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.
Vehicle Service and Care 9-55
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