2009 GMC SIERRA wheel

20-Inch Tires
If your vehicle has the optional 20-inch
P275/55R20 size tires, they are classied as
touring tires and are designed for on road use. The
low-prole, wide tread design is not recommended
for “off-road” driving or commercial uses such
as snow plowing. SeeOff-Road Driving on
page 4-12andAdding a Snow Plow or Similar
Equipment on page 4-38for additional information.
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 ination pressure
and, when possible avoid contact with curbs,
potholes, and other road hazards.
Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustrations are examples
of a typical P-Metric and a LT-Metric tire sidewall.
(A) Tire Size
:The tire size code 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.
Passenger (P-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 light truck (LT-Metric) tire
illustration, it would mean that the tire’s sidewall is
75 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
:The service description
indicates the load range and speed rating of a
tire. The load index represents the load carry
capacity a tire is certied to carry. The load index
can range from 1 to 279. The speed rating is
the maximum speed a tire is certied 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.
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.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
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Vehicles with P265/70R17 or P275/55R20 size tires
require ination pressure adjustment when driving the
vehicle at speeds of 100 mph (160 km/h) or higher.
Set the cold tire ination pressure to 3 psi (20 kPa)
above the recommended cold tire pressure shown on
the Tire and Loading Information label.
When you end this high-speed driving, return the tires
to the cold ination pressure shown on the Tire and
Loading Information label. SeeLoading the Vehicle on
page 4-32andInflation - Tire Pressure on page 5-73.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel bolt
or wheel nut is replaced, check the wheel nut torque after
100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km)
of driving. For proper torque and wheel nut tightening
information, seeRemoving the Spare Tire and Tools on
page 5-93.The outer tire on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more
evenly and last longer if you rotate the tires periodically,
seeTire Inspection and Rotation on page 5-81. Also
seeScheduled Maintenance (Gasoline Engine) on
page 6-4.
{CAUTION:
If you operate your vehicle with a tire that is badly
underinated, the tire can overheat. An overheated
tire can lose air suddenly or catch re. You or
others could be injured. Be sure all tires (including
the spare) are properly inated.
SeeInflation - Tire Pressure on page 5-73, for
information on proper tire ination.
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Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio
and sensor technology to check tire pressure levels.
The TPMS sensors monitor the air pressure in your
vehicle’s tires and transmit tire pressure readings to
a receiver located in the vehicle.
Each tire, including the spare (if provided), should be
checked monthly when cold and inated to the ination
pressure recommended by the vehicle manufacturer
on the vehicle placard or tire ination pressure label.
(If your vehicle has tires of a different size than the size
indicated on the vehicle placard or tire ination
pressure label, you should determine the proper tire
ination pressure for those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system (TPMS)
that illuminates a low tire pressure telltale when one
or more of your tires is signicantly under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires as
soon as possible, and inate them to the proper
pressure. Driving on a signicantly under-inated tire
causes the tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling
and stopping ability.Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-ination has
not reached the level to trigger illumination of the
TPMS low tire pressure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is
not operating properly. The TPMS malfunction indicator
is combined with the low tire pressure telltale. When
the system detects a malfunction, the telltale will
ash for approximately one minute and then remain
continuously illuminated. This sequence will continue
upon subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the system
may not be able to detect or signal low tire pressure as
intended. TPMS malfunctions may occur for a variety
of reasons, including the installation of replacement or
alternate tires or wheels on the vehicle that prevent the
TPMS from functioning properly. Always check the TPMS
malfunction telltale after replacing one or more tires or
wheels on your vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to continue to
function properly.
SeeTire Pressure Monitor Operation on page 5-77for
additional information.
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Federal Communications Commission
(FCC) and Industry and Science Canada
The Tire Pressure Monitor System (TPMS) operates
on a radio frequency and complies with Part 15 of
the FCC Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
The TPMS operates on a radio frequency and complies
with RSS-210 of Industry and Science Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
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
transmits the tire pressure readings to a receiver
located in the vehicle.
When a low tire pressure
condition is detected, the
TPMS will illuminate the
low tire pressure warning
symbol located on the
instrument panel cluster.
At the same time a message to check the pressure in a
specic tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and the
DIC warning message come on at each ignition cycle
until the tires are inated to the correct ination pressure.
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One or more TPMS sensors are missing or
damaged. The DIC message and 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 5-84.
Operating electronic devices or being near facilities
using radio wave frequencies similar to the TPMS
could cause the TPMS sensors to malfunction.
If the TPMS is not functioning it cannot detect or signal a
low tire condition. See your dealer/retailer for service if
the TPMS malfunction light and DIC message comes on
and stays on.
TPMS Sensor Matching Process
Each TPMS sensor has a unique identication code.
Any time you rotate your vehicle’s tires or replace one or
more of the TPMS sensors, the identication 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. If increasing the tire’s air pressure, do not
exceed the maximum ination pressure indicated on the
tire’s sidewall.
To decrease air-pressure out of a tire you can use the
pointed end of the valve cap, a pencil-style air pressure
gage, or a key.
You have two minutes to match the rst tire/wheel
position, and ve minutes overall to match all four
tire/wheel positions. If it takes longer than two minutes, to
match the rst tire and wheel, or more than ve minutes
to match all four tire and wheel positions the matching
process stops and you need to start over.
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The TPMS sensor matching process is outlined below:
1. Set the parking brake.
2. Turn the ignition switch to ON/RUN with the
engine off.
3. Press the Remote Keyless Entry (RKE) transmitter’s
LOCK and UNLOCK buttons at the same time for
approximately ve seconds. The horn sounds twice
to signal the receiver is in relearn mode and TIRE
LEARNING ACTIVE message displays on the DIC
screen.
If your vehicle does not have RKE, press the Driver
Information Center (DIC) vehicle information button
until the PRESS
VTO RELEARN TIRE POSITIONS
message displays. The horn sounds twice to signal
the receiver is in relearn mode and TIRE LEARNING
ACTIVE message displays on the DIC screen.
If your vehicle does not have RKE or DIC buttons,
press the trip odometer reset stem located on the
instrument panel cluster until the PRESS
VTO
RELEARN TIRE POSITIONS message displays.
The horn sounds twice to signal the receiver is in
relearn mode and TIRE LEARNING ACTIVE
message displays on the DIC screen.
4. Start with the driver side front tire.5. Remove the valve cap from the valve cap stem.
Activate the TPMS sensor by increasing or
decreasing the tire’s air pressure for ve seconds,
or until a horn chirp sounds. The horn chirp,
which may take up to 30 seconds to sound,
conrms that the sensor identication code has
been matched to this tire and wheel position.
6. Proceed to the passenger side front tire, and repeat
the procedure in Step 5.
7. Proceed to the passenger side rear tire, and repeat
the procedure in Step 5.
8. Proceed to the driver side rear tire, and repeat the
procedure in Step 5. The horn sounds two times to
indicate the sensor identication code has been
matched to the driver side rear tire, and that the
TPMS sensor matching process is no longer active.
The TIRE LEARNING ACTIVE message on the DIC
display screen goes off.
9. Turn the ignition switch to LOCK/OFF.
10. Set all four tires to the recommended air pressure
level as indicated on the Tire and Loading
Information label.
11. Put the valve caps back on the valve stems.
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Tire Inspection and Rotation
We recommend that you regularly inspect your
vehicle’s tires, including the spare tire, for signs of
wear or damage. SeeWhen It Is Time for New
Tires on page 5-83for more information.
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km). SeeScheduled Maintenance
(Gasoline Engine) on page 6-4.
The purpose of a regular tire rotation is to achieve
a uniform wear for all tires on the vehicle. This
will ensure that your vehicle continues to perform
most like it did when the tires were new.
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment.
Also check for damaged tires or wheels. SeeWhen
It Is Time for New Tires on page 5-83andWheel
Replacement on page 5-89.
If your vehicle has dual rear wheels, also seeDual
Tire Operation on page 5-75.If your vehicle has single rear wheels and the
tread design for the front tires is the same as the
rear tires, use the rotation pattern shown here
when rotating the tires.
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