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
certi ed to carry. The speed
rating is the maximum speed a
tire is certi ed to carry a load.
Tire Terminology and
De nitions
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.
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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, see
Compact Spare Tire on
page 5-71.
How to Check
Use a good quality pocket-type
gage to check tire pressure.
You cannot tell if your tires
are properly in ated simply by
looking at them. Radial tires may
look properly in ated even when
they are under-in ated. Check
the tire’s in ation 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 in ation pressure
matches the recommended
pressure on the Tire and Loading
Information label, no further
adjustment is necessary. If the
in ation pressure is low, add air
until you reach the recommended
amount.
If you over ll 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
in ation 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 in ation pressure
for the vehicle load.
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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
and wheel assembly. The TPMS
sensors monitor the air pressure in
the vehicle’s tires and transmit the
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 on
the instrument panel cluster.The low tire pressure warning light
comes on at each ignition cycle
until the tires are in ated to
the correct in ation 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 may be an early indicator
that the air pressure in the tire(s)
are getting low and need to be
in ated to the proper pressure.
A Tire and Loading Information
label, attached to your vehicle,
shows the size of your vehicle’s
original equipment tires and
the correct in ation pressure for
your vehicle’s tires when they
are cold. SeeLoading the Vehicle
on page 4-28, for an example of the
Tire and Loading Information
label and its location on your
vehicle. Also seeInflation - Tire
Pressure on page 5-49.Your vehicle’s TPMS system can
warn you about a low tire pressure
condition but it does not replace
normal tire maintenance. SeeTire
Inspection and Rotation on
page 5-56andTires on page 5-43.
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.
TPMS Malfunction Light
The TPMS will not function properly
if one or more of the TPMS
sensors are missing or inoperable.
When the system detects a
malfunction, the low tire warning
light ashes for about one minute
and then stays on for the
remainder of the ignition cycle.
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The TPMS malfunction light comes
on at each ignition cycle until the
problem is corrected. Some of
the conditions that can cause the
malfunction light to come on are:
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a TPMS
sensor. The TPMS malfunction
light should go off once you
re-install the road tire containing
the TPMS sensor.
The TPMS sensor matching
process was started but not
completed or not completed
successfully after rotating the
vehicle’s tires. The TPMS
malfunction light should go
off once the TPMS sensor
matching process is performed
successfully. See “TPMS Sensor
Matching Process” later in this
section.
One or more TPMS sensors are
missing or damaged. The TPMS
malfunction light should go
off when the TPMS sensors
are installed and the sensor
matching process is performed
successfully. See your dealer/
retailer for service.
Replacement tires or wheels do
not match your vehicle’s original
equipment tires or wheels. Tires
and wheels other than those
recommended for your vehicle
could prevent the TPMS from
functioning properly. SeeBuying
New Tires on page 5-58.
Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identi cation code. Any time you
replace one or more of the TPMS
sensors or rotate the vehicle’s tires,
the identi cation codes will need to
be matched to the new tire/wheel
position. The sensors are matched,
to the tire/wheel positions, in the
following order: driver side front tire,
passenger side front tire, passenger
side rear tire, and driver side rear tire
using a TPMS diagnostic tool. See
your dealer/retailer for service.
The TPMS sensors can also be
matched to each tire/wheel position
by increasing or decreasing the
tire’s air pressure. When increasing
the tire’s pressure, do not exceed
the maximum in ation pressure
indicated on the tire’s sidewall.
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CAUTION (Continued)
When you change a wheel,
remove any rust or dirt from
places where the wheel attaches
to the vehicle. In an emergency,
you can use a cloth or a paper
towel to do this; but be sure to
use a scraper or wire brush later,
if needed, to get all the rust or dirt
off. SeeChanging a Flat Tire on
page 5-64.
When It Is Time for New
Tires
Various factors, such as
maintenance, temperatures, driving
speeds, vehicle loading, and
road conditions in uence when
you need new tires.One way to tell when it is time for
new tires is to check the treadwear
indicators, which will appear when
the tires have only 1/16 inch
(1.6 mm) or less of tread remaining.
You need new tires if any of the
following statements are true:
You can see the indicators at
three or more places around
the tire.
You can see cord or fabric
showing through the tire’s rubber.
The tread or sidewall is cracked,
cut, or snagged deep enough to
show cord or fabric.
The tire has a bump, bulge, or
split.
The tire has a puncture, cut, or
other damage that cannot be
repaired well because of the size
or location of the damage.
The rubber in tires degrades over
time, even if they are not being
used. This is also true for the spare
tire, if the vehicle has one. Multiple
conditions affect how fast this
aging takes place, including
temperatures, loading conditions,
and in ation pressure maintenance.
With proper care and maintenance
tires typically wear out before
they degrade due to age. If you are
unsure about the need to replace
the tires as they get older, consult
the tire manufacturer for more
information.
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Wheel Replacement
Replace any wheel that is bent,
cracked or badly rusted or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts
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 your
wheels, wheel bolts or wheel
nuts, replace them only with new
Saturn original equipment parts.
This way, you will be sure to have
the right wheel, wheel bolts and
wheel nuts for your vehicle.{CAUTION
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts on your vehicle can be
dangerous. It could affect the
braking and handling of your
vehicle, make your tires lose air
and make you lose control. You
could have a collision in which
you or others could be injured.
Always use the correct wheel,
wheel bolts, and wheel nuts for
replacement.
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 5-64for more information.
Used Replacement Wheels
{CAUTION
Putting a used wheel on your
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 Saturn 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.
(Continued)
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CAUTION (Continued)
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.
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.
If a Tire Goes Flat
It is unusual for a tire to blowout
while you are driving, especially if
you maintain your vehicle’s tires
properly. If air goes out of a tire, it is
much more likely to leak out slowly.
But if you should ever have a
blowout, here are a few tips about
what to expect and what to do:
If a front tire fails, the at tire creates
a drag that pulls the vehicle toward
that side. Take your foot off the
accelerator pedal and grip the
steering wheel rmly. Steer to
maintain lane position, and then
gently brake to a stop well out of
the traffic lane.
A rear blowout, particularly on a
curve, acts much like a skid and may
require the same correction you
would use in a skid. In any rear
blowout remove your foot from the
accelerator pedal. Get the vehicle
under control by steering the
way you want the vehicle to go.It may be very bumpy and noisy, but
you can still steer. Gently brake to a
stop, well off the road if possible.
{CAUTION
Lifting a vehicle and getting under
it to do maintenance or repairs is
dangerous without the appropriate
safety equipment and training. If a
jack is provided with the vehicle, it
is designed only for changing a
at tire. If it is used for anything
else, you or others could be badly
injured or killed if the vehicle slips
off the jack. If a jack is provided
with the vehicle, only use it for
changing a at tire.
If a tire goes at, the next part
shows how to use the jacking
equipment to change a at tire
safely.
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Aluminum Wheels
Notice:Chrome wheels and
other chrome trim may be
damaged if the vehicle is not
washed after driving on roads
that have been sprayed with
magnesium, calcium or sodium
chloride. These chlorides are
used on roads for conditions
such as ice and dust. Always
wash the vehicle’s chrome with
soap and water after exposure.
Notice:Using strong soaps,
chemicals, abrasive polishes,
cleaners, brushes, or cleaners
that contain acid on aluminum or
chrome-plated wheels, could
damage the surface of the
wheel(s). The repairs would not
be covered by the vehicle
warranty. Use only approved
cleaners on aluminum or
chrome-plated wheels.Keep the wheels clean using a soft
clean cloth with mild soap and
water. Rinse with clean water. After
rinsing thoroughly, dry with a soft
clean towel. A wax may then
be applied.
Notice:Using chrome polish on
aluminum wheels could damage
the wheels. The repairs would
not be covered by the vehicle
warranty. Use chrome polish on
chrome wheels only.
The surface of these wheels is
similar to the painted surface of the
vehicle. Do not use strong soaps,
chemicals, abrasive polishes,
abrasive cleaners, cleaners with
acid, or abrasive cleaning brushes
on them because the surface
could be damaged. Do not use
chrome polish on aluminum wheels.Notice:Driving the vehicle
through an automatic car wash
that has silicone carbide tire
cleaning brushes, could damage
the aluminum or chrome-plated
wheels. The repairs would not be
covered by the vehicle warranty.
Never drive a vehicle that has
aluminum or chrome-plated
wheels through an automatic car
wash that uses silicone carbide
tire cleaning brushes.
Tires
To clean the tires, use a stiff brush
with tire cleaner.
Notice:Using petroleum-based
tire dressing products on the
vehicle may damage the paint
nish and/or tires. When applying
a tire dressing, always wipe off
any overspray from all painted
surfaces on the vehicle.
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