2008 GMC SIERRA 5-81

OUTPUT shows the power output to the trailer anytime
a trailer with electric brakes is connected. Output is
displayed in 0 to 10 bars. Dashes may appear in
the OUTPUT display. See “Integrated Trailer Brake
Control System” underTowing a Trailer on page 4-55
for more information.
Oil Life
To access this display, the vehicle must be in PARK (P).
Press the trip odometer reset stem until OIL LIFE
REMAINING displays. This display shows an estimate
of the oil’s remaining useful life. If you see 99% OIL LIFE
REMAINING on the display, that means 99% of the
current oil life remains. The engine oil life system
will alert you to change the oil on a schedule consistent
with your driving conditions.
When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 3-63. You should
change the oil as soon as you can. SeeEngine
Oil (Gasoline Engine) on page 5-15. In addition to the
engine oil life system monitoring the oil life, additional
maintenance is recommended in the Maintenance
Schedule in this manual. SeeScheduled Maintenance
(Gasoline Engine) on page 6-4for more information.
Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.Also, be careful not to reset the OIL LIFE display
accidentally at any time other than when the oil has just
been changed. It cannot be reset accurately until the
next oil change. To reset the engine oil life system, see
Engine Oil Life System on page 5-18.
Relearn Tire Positions
Your vehicle may have this display. To access this
display, the vehicle must be in PARK (P). If your vehicle
has the Tire Pressure Monitor System (TPMS), after
rotating the tires or after replacing a tire or sensor, the
system must re-learn the tire positions. To re-learn
the tire positions, seeTire Pressure Monitor System on
page 5-76. SeeTire Inspection and Rotation on
page 5-81andDIC Warnings and Messages on
page 3-63for more information.
Relearn Remote Key
To access this display, the vehicle must be in PARK (P).
This display allows you to match Remote Keyless
Entry (RKE) transmitters to your vehicle. To match an
RKE transmitter to your vehicle:
1. Press the trip odometer reset stem until RELEARN
REMOTE KEY displays.
2. Press and hold the trip odometer reset stem for
three seconds.
The message REMOTE KEY LEARNING ACTIVE
will display.
3-62

TIRE LEARNING ACTIVE
If your vehicle has the Tire Pressure Monitor System
(TPMS), this message displays when the system
is re-learning the tire positions on your vehicle. See
“DIC Operation and Displays (Without DIC Buttons)”
earlier in this section for more information. The tire
positions must be re-learned after rotating the tires or
after replacing a tire or sensor. SeeTire Inspection and
Rotation on page 5-81,Tire Pressure Monitor System
on page 5-76, andInflation - Tire Pressure on page 5-74
for more information.
TRACTION CONTROL OFF
If your vehicle has StabiliTrak®, this message displays
when the Traction Control System (TCS) is turned
off. Adjust your driving accordingly. SeeStabiliTrak
®
System on page 4-6for more information.
TRAILER CONNECTED
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message displays briey when
a trailer with electric brakes is rst connected to
the vehicle.
This message clears itself after several seconds. This
message also clears if you acknowledge it. After
this message clears, the TRAILER GAIN/OUTPUT
display appears in the DIC.See “TRAILER GAIN/OUTPUT” underDIC Operation
and Displays (With DIC Buttons) on page 3-55or
DIC Operation and Displays (Without DIC Buttons) on
page 3-60and “Integrated Trailer Brake Control System”
underTowing a Trailer on page 4-55for more
information.
TRANSMISSION HOT IDLE ENGINE
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed on
the instrument panel cluster and/or DIC, you
can damage the transmission. This could lead to
costly repairs that would not be covered by
your warranty. Do not drive your vehicle with
overheated transmission uid or while the
transmission temperature warning is displayed.
This message displays along with a continuous chime if
the transmission uid in the vehicle gets hot. Driving
with the transmission uid temperature high can cause
damage to the vehicle. Stop the vehicle and let it
idle to allow the transmission to cool. This message
clears and the chime stops when the uid temperature
reaches a safe level.
3-71

Headlamp Aiming...........................................5-56
Bulb Replacement..........................................5-59
Halogen Bulbs..............................................5-59
Headlamps..................................................5-60
Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp.............................................5-61
Pickup Box Identication and Fender
Marker Lamps...........................................5-62
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-62
License Plate Lamp......................................5-64
Replacement Bulbs.......................................5-65
Windshield Wiper Blade Replacement..............5-65
Tires..............................................................5-66
Tire Sidewall Labeling...................................5-67
Tire Terminology and Denitions.....................5-71
Ination - Tire Pressure.................................5-74
Dual Tire Operation.......................................5-76
Tire Pressure Monitor System.........................5-76
Tire Pressure Monitor Operation.....................5-78
Tire Inspection and Rotation...........................5-81
When It Is Time for New Tires.......................5-84
Buying New Tires.........................................5-84Different Size Tires and Wheels......................5-86
Uniform Tire Quality Grading..........................5-86
Wheel Alignment and Tire Balance..................5-88
Wheel Replacement......................................5-88
Tire Chains..................................................5-90
If a Tire Goes Flat........................................5-91
Changing a Flat Tire.....................................5-92
Removing the Spare Tire and Tools................5-93
Removing the Flat Tire and Installing the
Spare Tire................................................5-98
Secondary Latch System..............................5-105
Storing a Flat or Spare Tire and Tools...........5-108
Spare Tire.................................................5-112
Appearance Care
..........................................5-112
Interior Cleaning.........................................5-112
Fabric/Carpet..............................................5-114
Leather......................................................5-114
Instrument Panel, Vinyl, and Other Plastic
Surfaces.................................................5-115
Care of Safety Belts....................................5-115
Weatherstrips.............................................5-115
Washing Your Vehicle..................................5-116
Cleaning Exterior Lamps/Lenses....................5-116
Finish Care................................................5-116
Section 5 Service and Appearance Care
5-2

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, see
Removing 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 see
Scheduled 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 5-74, for
information on proper tire ination.
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.
5-76

Tire Pressure Monitor Operation
The Tire Pressure Monitor System (TPMS), if your
vehicle has this feature, 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.If your vehicle has DIC buttons, tire pressure levels can
be viewed by the driver. For additional information and
details about the DIC operation and displays seeDIC
Operation and Displays (With DIC Buttons) on page 3-55
orDIC Operation and Displays (Without DIC Buttons)
on page 3-60andDIC Warnings and Messages
on page 3-63.
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 could be an early indicator
that the air pressure in the tire(s) are getting low and
need to be inated 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 ination pressure for
your vehicle’s tires when they are cold. SeeLoading
Your Vehicle on page 4-36, for an example of the Tire
and Loading Information label and its location on
your vehicle. Also seeInflation - Tire Pressure
on page 5-74.
Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal tire
maintenance. SeeTire Inspection and Rotation on
page 5-81andTires on page 5-66.
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.
5-78

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.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 5-84for 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 5-84
andWheel Replacement on page 5-88.
If your vehicle has dual rear wheels, also seeDual
Tire Operation on page 5-76.
5-81

number is molded onto the tire’s sidewall near the tire
size. If the tires have an all-season tread design, the
TPC spec number will be followed by a MS, for mud and
snow. SeeTire Sidewall Labeling on page 5-67for
additional information.
GM recommends replacing tires in sets of four
(or six if your vehicle has dual rear wheels). This is
because uniform tread depth on all tires will help keep
your vehicle performing most like it did when the tires
were new. Replacing less than a full set of tires can affect
the braking and handling performance of your vehicle.
SeeTire Inspection and Rotation on page 5-81for
information on proper tire rotation.
{CAUTION:
Mixing tires could cause you to lose
control while driving. If you mix tires of
different sizes, brands, or types (radial
and bias-belted tires) the vehicle may not
handle properly, and you could have a
crash. Using tires of different sizes,
brands, or types may also cause damage to
your vehicle. Be sure to use the correct
size, brand, and type of tires on your
vehicle’s wheels.
{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.
If you must replace your vehicle’s tires with those that
do not have a TPC Spec number, make sure they are
the same size, load range, speed rating, and construction
type (radial and bias-belted tires) as your vehicle’s
original tires.
Vehicles that have a tire pressure monitoring system
could give an inaccurate low-pressure warning if
non-TPC Spec rated tires are installed on your vehicle.
Non-TPC Spec rated tires may give a low-pressure
warning that is higher or lower than the proper warning
level you would get with TPC Spec rated tires. See
Tire Pressure Monitor System on page 5-76.
Your vehicle’s original equipment tires are listed on the
Tire and Loading Information label. SeeLoading Your
Vehicle on page 4-36, for more information about the
Tire and Loading Information label and its location on
your vehicle.
5-85

MaintenanceI— Use MaintenanceIif the
CHANGE ENGINE OIL SOON message comes
on within 10 months since the vehicle was purchased
or MaintenanceIIwas performed.MaintenanceII— Use MaintenanceIIif the previous
service performed was MaintenanceI. Always use
MaintenanceIIwhenever the message comes on
10 months or more since the last service or if the
message has not come on at all for one year.
Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil (Gasoline Engine) on page 5-15.
Reset oil life system. SeeEngine Oil Life System on page 5-18.An Emission
Control Service.••
Allison Transmission
®only: Replace external transmission lter at the rst
maintenance service performed on the vehicle.
Lubricate chassis components.See footnote #.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter or change indicator (if equipped). If
necessary, replace lter. SeeEngine Air Cleaner/Filter (Gasoline Engines) on
page 5-19.See footnote (p).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-81and “Tire Wear Inspection” inAt Least Once a Month
on page 6-12.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid
as needed.••
6-5