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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. SeeAll-Wheel Drive (AWD)
System on page 4-11for 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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(C) Aspect Ratio:A two-digit number that indicates the
tire height-to-width measurements. For example, if
the tire size aspect ratio is “75,” as shown in item “C” 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
“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: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 “A” to “Z”. The light truck tire size example
above shows dual or single tire con gurations.(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letter “LT” 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.Light Truck (LT-Metric) Tire
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(C) Aspect Ratio:A two-digit number that indicates the
tire height-to-width measurements. For example, if
the tire size aspect ratio is “75,” as shown in item “C” 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
“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: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 “A” to “Z”. 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.
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.
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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 5-96.
{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
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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 5-78for more
information.
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 “S” 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.
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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 “Storing the
Flat Tire on an All-Wheel-Drive Vehicle” 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 “Storing the Spare Tire and Tools”
and “Storing the Flat Tire on a Front-Wheel Drive
Vehicle” 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
“Secondary Latch System” later in this section.
To continue changing the at tire see “Removing the
Flat Tire and Installing the Spare Tire” 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 “Storing a Flat or Spare Tire and Tools”
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 “Storing the Spare Tire and Tools” later in
this section for instructions. To store a at full-size tire
correctly, see “Storing the Flat Tire on an
All-Wheel-Drive Vehicle” 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.
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