wheel size SATURN L-SERIES 2005 Owners Manual

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 first 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 range and speed rating of the tire. The load
index represents the load carry capacity a tire is certified
to carry. The load index can range from 1 to 279. The
speed rating is the maximum speed a tire is certified
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.
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After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the Tire and
Loading Information label. SeeLoading Your Vehicle
on page 4-32, for an example of the tire and loading
information label and its location on your vehicle.
Make certain that all wheel bolts are properly tightened.
See “Wheel Bolt Torque” underCapacities and
Specications on page 5-89.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel bolts
become loose after a time. The wheel could
come off and cause an accident. 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 you need to,
to get all the rust or dirt off. SeeChanging a
Flat Tire on page 5-62.
When It Is Time for New Tires
One way to tell when it’s
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining.
You need a new tire 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
can’t be repaired well because of the size or
location of the damage.
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Buying New Tires
To find out what kind and size of tires your vehicle
needs, look at the tire and loading information label.
For more information about this label and its location on
your vehicle, seeLoading Your Vehicle on page 4-32.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specification (TPC Spec)
number on each tire’s sidewall. When you get new
tires, GM recommends that you get tires with that same
TPC Spec number. That way your vehicle will continue
to have tires that are designed to give proper endurance,
handling, speed rating, load range, traction, ride and
other things during normal service on your vehicle.
If your tires have an all-season tread design, the TPC
number will be followed by an “MS” (for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires
on all wheels. It’s all right to drive with your
compact spare temporarily, it was developed
for use on your vehicle. SeeCompact Spare
Tire on page 5-72.
{CAUTION:
If you use bias-ply tires on your 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 your vehicle.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can’t know how it’s been used
or how far it’s 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:
Don’t use tire chains. There’s 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. The area damaged by the
tire chains could cause you to lose control of
your 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 your
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it’s contacting your vehicle, and
don’t spin your wheels. If you do nd traction
devices that will t, install them on the
front tires.
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3. Place the flat tire, face down, into the spare tire
compartment. When placing an aluminum flat tire
into the spare tire compartment, be very careful
to avoid scraping the wheel face on the hold-down
bolt and other hard surfaces. The hold-down
bolt should pass through the rear most wheel vent
hold. The flat tire will protrude above the trunk
floor in this position.
4. Place the nut onto the hold-down bolt and tighten
down until it is snug.
The compact spare is for temporary use only. Replace
the compact spare tire with a full-size tire as soon
as you can. See the storage instructions label to replace
your compact spare into your trunk or cargo area
separately.
Store the flat tire in the compact spare tire compartment
and secure the adapter, extension (aluminum wheel
only) and wing bolt. Store the jack and wheel wrench in
the foam tray.
Compact Spare Tire
Although the compact spare tire was fully inflated when
your vehicle was new, it can lose air after a time.
Check the inflation pressure regularly. It should be
60 psi (420 kPa).After installing the compact spare tire on your vehicle,
you should stop as soon as possible and make sure your
compact spare tire is correctly inflated. The compact
spare tire is made to perform well at speeds up to 65 mph
(105 km/h) for distances up to 3,000 miles (5 000 km), so
you can finish your trip and have your full-size tire
repaired or replaced where you want. Of course, it is best
to replace your spare with a full-size tire as soon as you
can. Your spare will last longer and be in good shape in
case you need it again.
Notice:When the compact spare is installed, do not
take your vehicle through an automatic car wash with
guide rails. The compact spare can get caught on the
rails. That can damage the tire and wheel, and maybe
other parts of your vehicle.
Do not use your compact spare tire on other vehicles.
And do not mix your compact spare tire or wheel
with other wheels or tires. They won’t fit. Keep your
compact spare tire and its wheel together.
Notice:Tire chains will not t your compact spare.
Using them can damage your vehicle and can
damage the chains too. Do not use tire chains on
your compact spare.
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