2004 Oldsmobile Silhouette wheel size

All-Wheel Drive Disable Warning
Message
Your vehicle may have this message. If it does, it will
come on when there is a spare tire on the vehicle, or
when the anti-lock brake system warning light comes on,
or when the rear differential ¯uid is overheating. This
message will go out when the differential ¯uid cools.
The all-wheel drive system will be disabled until the
compact spare tire is replaced by a full-size tire. If the
warning message is still on after putting on the full-size
tire, you need to reset the warning message. To reset the
warning message, turn the ignition off and then back on
again. If the message stays on, see your dealer right
away. See
All-Wheel Drive (AWD) System on page 4-10for more information.
Low Fuel Warning Message
If your fuel is low, the warning message will come on
and stay on until you add fuel.
If the warning message is still on after adding fuel,
you need to reset the warning message. To reset the
warning message, turn the ignition off and then back on.
If the message stays on, see your dealer. United StatesCanada
United StatesCanada
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(F) Tire Size:A combination of letters and numbers
de®ne a tire's width, height, aspect ratio, construction
type and service description. The letter ªTº as the
®rst character in the tire size means the tire is for
temporary use only.
(G) Tire Performance Criteria Speci®cation
(TPC Spec):Original equipment tires designed to
GM's speci®c tire performance criteria have a
TPC speci®cation code molded onto the sidewall.
GM's TPC speci®cations meet or exceed all federal
safety guidelines.
Tire Size
The following examples show the different parts of
a tire size.(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter ªPº 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 ª75,º as shown in item ªCº
of the illustration, it would mean that the tire's sidewall
is 75% 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
ªRº means radial ply construction; the letter ªDº means
diagonal or bias ply construction; and the letter ªBº means
belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from ªAº to ªZº. The light truck tire size example
above shows dual or single tire con®gurations.
Passenger (P-Metric) Tire
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(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letter ªLTº
as the ®rst two characters in the tire size means a light
truck 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 ª75,º as shown in item ªCº
of the illustration, it would mean that the tire's sidewall
is 75% 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
ªRº means radial ply construction; the letter ªDº means
diagonal or bias ply construction; and the letter ªBº
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from ªAº to ªZº. The light truck tire size example
above shows dual or single tire con®gurations.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. Light Truck (LT-Metric) Tire
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{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. See ªCompact
Spare Tireº in the index.
{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.
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, which grades tires by
treadwear, traction and temperature performance.
(This applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
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.
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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 GM original equipment wheel.
Tire Chains
Notice:Use tire chains only where legal and only
when you must. Use only SAE Class ªSº type chains
that are the proper size for your tires. Install them on
the front tires and tighten them as tightly as possible
with the ends securely fastened. Drive slowly and
follow the chain manufacturer's instructions. If you
can hear the chains contacting your vehicle, stop and
retighten them. If the contact continues, slow down
until it stops. Driving too fast or spinning the wheels
with chains on will damage your vehicle.
Accessory In¯ator
Your vehicle may have an accessory in¯ator. With it, you
can in¯ate things like air mattresses and basketballs,
and you can also use it to bring your tires up to the proper
pressure.
The accessory in¯ator is located in the rear
compartment on the driver's side. To remove the
protective cap, pull the tab on the cap.
This symbol is on the
accessory in¯ator switch.
There may be an accessory in¯ator kit stored in the
glove box. It includes a 20-foot (6 m) hose with an
air pressure gage and nozzle adapters.
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3. To remove the compact spare tire from the cable,
tilt the retainer at the end of the cable so it can be
pulled up through the wheel opening.
4. If your vehicle is an AWD vehicle, after removing
the compact spare tire, turn the wrench clockwise
to raise the cable back up.On an AWD vehicle, you can not store a full-size
tire under the vehicle. It should be stowed inside
the vehicle by the cable provided. See ªStoring the
Flat Tire on an All-Wheel-Drive Vehicleº later in
this section.
If you have a front-wheel-drive vehicle, the hoist is
used to store a full-size or a ¯at road tire under
the vehicle. See ªStoring the Spare Tire and Toolsº
and ªStoring the Flat Tire on a Front-Wheel Drive
Vehicleº later in this section.
If the compact spare tire will not lower, check under the
vehicle to see if the tire is hanging loose and the
cable end and spring under the wheel plate are missing.
If so, the secondary latch system is engaged. See
ªSecondary Latch Systemº later in this section.
To continue changing the ¯at tire see ªRemoving the Flat
Tire and Installing the Spare Tireº later in this section.
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Secondary Latch System
Your vehicle may have an underbody mounted tire hoist
assembly equipped with a secondary latch system. It
is designed to stop a tire from suddenly falling off your
vehicle if the cable holding the spare tire is damaged.
For the secondary latch to work, the tire must be stowed
with the valve stem pointing down.
Front-wheel-drive vehicles use the underbody tire hoist
assembly to store either the compact spare or a ¯at
road tire. See ªStoring a Flat or Spare Tire and Toolsº
later in this section for instructions on storing the
spare or ¯at tire correctly.
If your vehicle is equipped with AWD, the underbody
tire hoist assembly stores only the compact spare
tire. See ªStoring the Spare Tire and Toolsº later in
this section for instructions. To store a ¯at full-size
tire correctly, see ªStoring the Flat Tire on an
All-Wheel-Drive Vehicleº later in this section.{CAUTION:
Before beginning this procedure read all the
instructions. Failure to read and follow the
instructions could damage the hoist assembly
and you and others could get hurt. Read and
follow the instructions listed below.
To release the spare tire from the secondary latch,
do the following:
{CAUTION:
Someone standing too close during the
procedure could be injured by the jack.
If the spare tire does not slide off the jack
completely, make sure no one is behind you
or on either side of you as you pull the jack
out from the spare.
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To put the cover back on, line up the tabs on the right
of the cover with the slots in the cover opening. Push the
cover in place and push down the tab so that it rests
in the groove. This secures the cover in place.
A. Strap
B. Bag and ToolsC. JackStore the center cap or the plastic bolt-on wheel covers
until a full size tire is put back on the vehicle. When you
replace the compact spare with a full-size tire, reinstall
the bolt-on wheel covers or the center cap. Hand-tighten
them over the wheel nuts, using the folding wrench.
Storing the Flat Tire on a Front-Wheel
Drive Vehicle
Follow the previously listed procedure for storing a
spare tire.
Storing the Flat Tire on an All-Wheel-Drive
Vehicle
1. Remove the tire storage bag and cable package
from the jack storage area.
2. If the vehicle has aluminum wheels, remove the
small center cap by tapping the back of the cap
with the extension of the shaft.
3. Put the ¯at tire in the tire storage bag and place it
in the rear storage area with the valve stem pointing
toward the front of the vehicle.
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