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
Object Detection Systems...............................2-63
Ultrasonic Rear Parking Assist (URPA)............2-63
OnStar
®System.............................................2-65
Universal Home Remote System......................2-68
Universal Home Remote System.....................2-68
Universal Home Remote System Operation
(With Three Round LED)............................2-69Storage Areas................................................2-74
Glove Box...................................................2-74
Cupholder(s)................................................2-75
Instrument Panel Storage...............................2-75
Center Console Storage.................................2-76
Luggage Carrier...........................................2-76
Rear Seat Armrest........................................2-77
Cargo Management System...........................2-78
Sunroof.........................................................2-79
Section 2 Features and Controls
2-2
Notice:Using a tool to force the key from the
ignition switch could cause damage or break the
key. Use the correct key and turn the key only with
your hand. Make sure the key is all the way in. If
it is, turn the steering wheel left and right while you
turn the key hard. If none of this works, then
your vehicle needs service.
B (ACC/ACCESSORY):This position lets things like
the radio and the windshield wipers operate while
the engine is off.
Lengthy operation of features such as the radio in the
ACC/ACCESSORY ignition position and the ON/RUN
position may drain the battery and prevent your vehicle
from starting. Do not operate your vehicle in the ACC/
ACCESSORY ignition position for a long period of time.
C (ON/RUN):This is the position for driving. It is the
position the ignition switch returns to after the engine
starts, and the key is released.
The battery could be drained if you leave the key in the
ACC/ACCESSORY or ON/RUN position with the
engine off. You may not be able to start your vehicle if
the battery is allowed to drain for an extended period
of time.
D (START):This position starts the engine.Key In the Ignition
Never leave your vehicle with the keys inside, as it is an
easy target for joy riders or thieves. If you leave the
key in the ignition and park your vehicle, a chime
will sound, when you open the driver’s door. Always
remember to remove your key from the ignition and take
it with you. This will lock your ignition and transmission.
Also, always remember to lock the doors.
The battery could be drained if you leave the key in the
ignition while your vehicle is parked. You may not be
able to start your vehicle after it has been parked for an
extended period of time.
Retained Accessory Power (RAP)
The following vehicle accessories can be used for up to
10 minutes after the engine is turned off:
Audio System
Power Windows
OnStar®System (if equipped)
Sunroof (if equipped)
These features work when the key is in ON/RUN or
ACC/ACCESSORY. Once the key is turned from
ON/RUN to LOCK/OFF, the windows and sunroof
continue to work up to 10 minutes until any door
is opened. The radio continues to work for up to
10 minutes or until the driver’s door is opened.
2-23
Sunroof
If your vehicle has a power sliding sunroof, the ignition
needs to be turned to RUN, or the Retained Accessory
Power (RAP) must be activated to open or close
the sunroof. When RAP is active, the sunroof will work
for 10 minutes after the ignition is turned off, or until
the driver’s door is opened. SeeRetained Accessory
Power (RAP) on page 2-23for more information.
Extended Cab
If your vehicle is an
extended-cab, the sunroof
switch is located on the
headliner above the
rearview mirror.
Vent:From the closed position, press and hold the rear
of the switch to vent the sunroof. To close the sunroof,
press and hold the front of the switch.Open:From the vent position, the sunroof can be fully
opened either manually or by using the express-open
feature. To open manually, press the rear of the switch
to the rst depression and hold until the sunroof has
reached the desired position. To open using
express-open, press the rear of the switch fully and
release. The sunroof will move to the full open position.
To stop the sunroof partway, press the switch a
second time.
Close:From the vent, or open position, press and hold
the front of the switch to close the sunroof.
The sunroof also has a roller sunshade that can be
used to block the rays of the sun. The roller sunshade
can be manually operated with the sunroof in an open or
closed position. To open the sunshade, press and
unlatch it, and roll it back. To close, pull it forward and
latch it into the closed position.
When the sunroof is opened, an air de ector will
automatically raise. The air de ector will retract when
the sunroof is closed.
2-79
Crew Cab
If your vehicle is a crew
cab, there are two sunroof
switches located in the
overhead console above
the rearview mirror.
Vent:From the closed position, press the rear of the
passenger’s side switch to vent the sunroof. To close the
sunroof, press and hold the front of the passenger’s
side switch.
Manual-Open/Manual-Close:To open the sunroof
press and hold the rear of the driver’s side switch until
the sunroof reaches the desired position. To close
the sunroof, press and hold the front of the driver’s side
switch until the sunroof reaches the desired position.
When the sunroof is opened, an air de ector will
automatically raise. The air de ector will retract when
the sunroof is closed.Express-Open/Express-Close:To express-open the
sunroof, fully press and release the rear of the
driver’s side switch. The sunroof will open automatically.
To stop the sunroof partway, press the switch a
second time. To express-close the sunroof, fully press
and release the front of the driver’s side switch. The
sunroof will close automatically. To stop the sunroof
partway, press the switch a second time.
The sunroof also has a sunshade which you can pull
forward to block sun rays. The sunshade must be
opened and closed manually.
Anti-Pinch Feature (Crew Cab Only):If an object is in
the path of the sunroof while it is closing, the anti-pinch
feature will detect the object and stop the sunroof
from closing at the point of the obstruction. The sunroof
will then open halfway, and the air de ector will raise.
To close the sunroof once it has re-opened, refer to the
Express-Close or Manual-Close functions described
previously. If the sunroof is in the vent position,
and there is an object in the path of the sunroof when it
closing, the anti-pinch feature will detect the object
and stop the sunroof. To close the sunroof once it has
stopped, refer to the Vent functions described
previously.
2-80