Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-3
Rear Seats
..............................................1-12
Safety Belts
.............................................1-14
Child Restraints
.......................................1-35
Airbag System
.........................................1-68
Restraint System Check
............................1-87
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
......................................2-10
Windows
.................................................2-15
Theft-Deterrent Systems
............................2-18
Starting and Operating Your Vehicle
...........2-22
Mirrors
....................................................2-55
Object Detection Systems
..........................2-63
OnStar
®System
......................................2-65
Universal Home Remote System
................2-68
Storage Areas
.........................................2-74
Sunroof
..................................................2-79
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-25
Warning Lights, Gages, and Indicators
........3-34
Driver Information Center (DIC)
..................3-54
Audio System(s)
.......................................3-80Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-50
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-4
Fuel
......................................................... 5-6
Checking Things Under the Hood
...............5-12
Rear Axle
...............................................5-51
Four-Wheel Drive
.....................................5-52
Front Axle
...............................................5-54
Noise Control System
...............................5-56
Headlamp Aiming
.....................................5-56
Bulb Replacement
....................................5-59
Windshield Wiper Blade Replacement
.........5-65
Tires
......................................................5-66
Appearance Care
...................................5-112
Vehicle Identi cation
...............................5-121
Electrical System
....................................5-122
Capacities and Speci cations
...................5-130
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-14
Vehicle Data Recording and Privacy
...........7-16
Index................................................................ 1
2008 GMC Sierra Owner ManualM
Keys...............................................................2-3
Remote Keyless Entry (RKE) System................2-4
Remote Keyless Entry (RKE) System
Operation...................................................2-5
Remote Vehicle Start......................................2-7
Doors and Locks............................................2-10
Door Locks..................................................2-10
Power Door Locks........................................2-10
Delayed Locking...........................................2-10
Programmable Automatic Door Locks..............2-11
Rear Door Security Locks..............................2-11
Lockout Protection........................................2-12
Rear Doors..................................................2-13
Tailgate.......................................................2-14
Windows........................................................2-15
Manual Windows..........................................2-16
Power Windows............................................2-16
Power Sliding Rear Window...........................2-17
Sun Visors...................................................2-18
Theft-Deterrent Systems..................................2-18
Content Theft-Deterrent.................................2-18
PASS-Key
®III+............................................2-20
PASS-Key®III+ Operation..............................2-20
Starting and Operating Your Vehicle................2-22
New Vehicle Break-In....................................2-22
Ignition Positions..........................................2-22Retained Accessory Power (RAP)...................2-23
Starting the Engine.......................................2-24
Fast Idle System..........................................2-25
Adjustable Throttle and Brake Pedal................2-26
Engine Coolant Heater..................................2-26
Active Fuel Management™.............................2-27
Automatic Transmission Operation...................2-28
Tow/Haul Mode............................................2-34
Four-Wheel Drive..........................................2-36
Parking Brake..............................................2-49
Shifting Into PARK (P)...................................2-50
Shifting Out of PARK (P)...............................2-52
Parking Over Things That Burn.......................2-53
Engine Exhaust............................................2-53
Running the Engine While Parked...................2-54
Mirrors...........................................................2-55
Manual Rearview Mirror.................................2-55
Automatic Dimming Rearview Mirror with
OnStar
®, Compass and Temperature
Display....................................................2-55
Automatic Dimming Rearview Mirror with
Compass and Temperature Display..............2-57
Outside Manual Mirrors..................................2-58
Outside Trailer-Tow Mirrors............................2-59
Outside Power Mirrors...................................2-59
Outside Power Foldaway Mirrors.....................2-61
Section 2 Features and Controls
2-1
Remote Keyless Entry (RKE)
System Operation
The vehicle’s doors can be locked and unlocked from
about 3 feet (1 m) up to 65 feet (20 m) away with
the Remote Keyless Entry (RKE) transmitter.
If your vehicle has the remote start feature you can also
start your vehicle with the RKE transmitter. The RKE
transmitter, with the remote start button, provides
an increased operating range of 195 feet (60 m) away.
However, the operating range may be less while the
vehicle is running. As a result, you may need to
be closer to your vehicle to turn it off than you were to
start it.
There are other conditions which can affect the
performance of the transmitter. SeeRemote Keyless
Entry (RKE) System on page 2-4.
/(Remote Vehicle Start):If your vehicle has this
feature, press
/to start the engine from outside the
vehicle using the RKE transmitter. SeeRemote
Vehicle Start on page 2-7for additional information.
Q(Lock):PressQto lock all the doors.
If enabled through the Driver Information Center (DIC),
the turn signal lamps will ash once to indicate
locking has occurred. If enabled through the DIC, the
horn will chirp when
Qis pressed again within
three seconds of the previous press of the lock button.With Remote Start
(Without Remote Start
Similar)
2-5
Battery Replacement
Replace the battery if the REPLACE BATTERY IN
REMOTE KEY message displays in the DIC. See
“REPLACE BATTERY IN REMOTE KEY” underDIC
Warnings and Messages on page 3-63for additional
information.
Notice:When replacing the battery, use care not to
touch any of the circuitry. Static from your body
transferred to these surfaces may damage the
transmitter.To replace the battery in the RKE transmitter:
1. Separate the halves of the transmitter with a at,
thin object inserted into the notch on the side.
2. Remove the old battery. Do not use a metal object.
3. Insert the new battery, positive side facing down.
Replace with a CR2032 or equivalent battery.
4. Put the transmitter back together tightly.
Remote Vehicle Start
Your vehicle may have a remote starting feature. This
feature allows you to start the engine from outside of the
vehicle. It may also start up the vehicle’s heating or
air conditioning systems and rear window defogger.
Normal operation of the system will return after the key
is turned to the ON/RUN position.
If your vehicle has an automatic climate control system,
the climate control system will default to a heating or
cooling mode depending on the outside temperatures. If
your vehicle does not have an automatic climate control
system, the system will turn on at the setting the vehicle
was set to when the vehicle was last turned off.
2-7
During a remote start, if your vehicle has an automatic
climate control system and heated seats, the heated
seats will turn on during colder outside temperatures and
will shut off when the key is turned to ON/RUN. If
your vehicle does not have an automatic climate control
system, during remote start, you will need to manually
turn the heated seats on and off. SeeHeated Seats
on page 1-6for additional information.
Laws in some communities may restrict the use of
remote starters. For example, some laws may require a
person using the remote start to have the vehicle in
view when doing so. Check local regulations for
any requirements on remote starting of vehicles.
Do not use the remote start feature if your vehicle is low
on fuel. Your vehicle may run out of fuel.
The RKE transmitter with the remote start button,
provides an increased range of operation. However, the
range may be less while the vehicle is running. As a
result, you may need to be closer to your vehicle to turn
it off, than you were to turn it on.
There are other conditions which can affect the
performance of the transmitter, seeRemote Keyless
Entry (RKE) System on page 2-4for additional
information./(Remote Start):This button will be on the RKE
transmitter if you have remote start.
To start the vehicle using the remote start feature:
1. Aim the transmitter at the vehicle.
2. Press and release the transmitter’s lock button. The
vehicle’s doors will lock. Immediately press and
hold the transmitter’s remote start button until the
turn signal lights ash. If you cannot see the
vehicle’s lights, press and hold the remote start
button for two to four seconds. Pressing the remote
start button again after the vehicle has started
will turn the engine off.
When the vehicle starts, the parking lamps will turn
on and remain on while the vehicle is running.
If the vehicle is left running it will automatically shut
off after 10 minutes unless a time extension has
been done.
3. If it is the rst remote start since the vehicle has
been driven, repeat these steps, while the engine
is still running, to extend the engine running time by
10 minutes. Remote start can be extended
one time.
After entering the vehicle during a remote start, insert
and turn the key to RUN to drive the vehicle.
2-8