2008 GMC SIERRA warning

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 Identication
...............................5-121
Electrical System
....................................5-122
Capacities and Specications
...................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

Using this Manual
Many people read the owner manual from beginning to
end when they rst receive their new vehicle. If this
is done, it can help you learn about the features
and controls for the vehicle. Pictures and words work
together in the owner manual to explain things.
If your vehicle has the DURAMAX
®Diesel engine, refer
to the DURAMAX®Diesel supplement for additional
and specic information on this engine.
Index
A good place to quickly locate information about the
vehicle is the Index in the back of the manual. It is an
alphabetical list of what is in the manual and the
page number where it can be found.
Safety Warnings and Symbols
There are a number of safety cautions in this book. A
box with the word CAUTION is used to tell about things
that could hurt you or others if you were to ignore the
warning.
{CAUTION:
These mean there is something that could hurt
you or other people.
We tell you what the hazard is and what to do to help
avoid or reduce the hazard. Please read these cautions.
If you do not, you or others could be hurt.
A circle with a slash
through it is a safety
symbol which means “Do
Not,” “Do Not do this”
or “Do Not let this happen.”
iii

Vehicle Damage Warnings
You will also nd notices in this manual.
Notice:These mean there is something that could
damage your vehicle.
A notice tells about something that can damage the
vehicle. Many times, this damage would not be covered
by your vehicle’s warranty, and it could be costly.
The notice tells what to do to help avoid the damage.
When you read other manuals, you might see
CAUTION and NOTICE warnings in different colors
or in different words.
There are also warning labels on the vehicle which use
the same words, CAUTION or NOTICE.
Vehicle Symbols
The vehicle has components and labels that use
symbols instead of text. Symbols are shown along with
the text describing the operation or information
relating to a specic component, control, message,
gage, or indicator.
iv

Rollover capable roof-rail airbags are designed to help
contain the head and chest of occupants in the
outboard seating positions in the rst and second rows.
The rollover capable roof-rail airbags are designed to
help reduce the risk of full or partial ejection in rollover
events, although no system can prevent all such
ejections.
But airbags would not help in many types of collisions,
primarily because the occupant’s motion is not
toward those airbags. SeeWhen Should an Airbag
Inflate? on page 1-73for more information.
Airbags should never be regarded as anything more
than a supplement to safety belts.
What Will You See After an Airbag
Inates?
After the frontal airbags inate, they quickly deate, so
quickly that some people may not even realize an
airbag inated. Roof-rail airbags may still be at least
partially inated for some time after they deploy. Some
components of the airbag module may be hot for
several minutes. For location of the airbag modules, see
What Makes an Airbag Inflate? on page 1-74.
The parts of the airbag that come into contact with you
may be warm, but not too hot to touch. There may
be some smoke and dust coming from the vents in the
deated airbags. Airbag ination does not preventthe driver from seeing out of the windshield or being
able to steer the vehicle, nor does it prevent people from
leaving the vehicle.
{CAUTION:
When an airbag inates, there may be dust in
the air. This dust could cause breathing
problems for people with a history of asthma or
other breathing trouble. To avoid this, everyone
in the vehicle should get out as soon as it is
safe to do so. If you have breathing problems
but cannot get out of the vehicle after an airbag
inates, then get fresh air by opening a window
or a door. If you experience breathing problems
following an airbag deployment, you should
seek medical attention.
Your vehicle has a feature that may automatically
unlock the doors, turn the interior lamps on, and turn
the hazard warning ashers on when the airbags inate.
You can lock the doors, turn the interior lamps off,
and turn the hazard warning ashers off by using the
controls for those features.
1-75

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

To manually shut off a remote start, do any of the
following:
Aim the RKE transmitter at the vehicle and press
the remote start button until the parking lamps
turn off.
Turn on the hazard warning ashers.
Turn the ignition switch on and then off.
The vehicle can be remote started two separate times
between driving sequences. The engine will run for
10 minutes after each remote start.
Or, you can extend the engine run time by another
10 minutes within the rst 10 minute remote start time
frame, and before the engine stops.
For example, if the lock button and then the remote
start buttons are pressed again after the vehicle
has been running for ve minutes, 10 minutes are
added, allowing the engine to run for 15 minutes.
The additional ten minutes are considered a second
remote vehicle start.
Once two remote starts, or a single remote start with
one time extension has been done, the vehicle must be
started with the key.
After the key is removed from the ignition, the vehicle
can be remote started again.The vehicle cannot be remote started if the key is in the
ignition, the hood is not closed, or if there is an
emission control system malfunction and the check
engine light comes on.
Also, the engine will turn off during a remote vehicle
start if the coolant temperature gets too high or if the oil
pressure gets low.
Vehicles that have the remote vehicle start feature are
shipped from the factory with the remote vehicle
start system enabled. The system may be enabled or
disabled through the DIC. See “REMOTE START” under
DIC Vehicle Customization (With DIC Buttons) on
page 3-72for additional information. If your vehicle does
not have DIC buttons, see your dealer/retailer to
enable or disable the remote vehicle start system.
Remote Start Ready
If your vehicle does not have the remote vehicle start
feature, it may have the remote start ready feature. This
feature allows your dealer/retailer to add the
manufacturer’s remote vehicle start feature.
If your vehicle has the remote start ready feature, the
RKE transmitter will have an extended range that allows
locking or unlocking of the vehicle from approximately
197 feet (60 m) away.
See your dealer/retailer if you would like to add the
manufacturer’s remote vehicle start feature to your
vehicle.
2-9

{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-49.
N (NEUTRAL):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-50orTowing
Your Vehicle on page 4-50for more information.
If the SERVICE 4–Wheel Drive message stays on, you
should take your vehicle to your dealer for service.
See “Service 4–Wheel Drive message” underDIC
Warnings and Messages on page 3-63.
Shifting Into Two-Wheel-Drive High
Turn the knob to the Two-Wheel-Drive High position.
This can be done at any speed, except when shifting
from Four-Wheel-Drive Low. See Shifting Out of
Four-Wheel-Drive Low for more information.
Shifting Into Four-Wheel Drive Low
When Four-Wheel-Drive Low is engaged, vehicle speed
should be kept below 45 mph. Extended high-speed
operation in Four-Wheel-Drive Low may damage
or shorten the life of the drivetrain.
To shift to the Four-Wheel-Drive Low position, the
ignition must be in RUN and the vehicle must be
stopped or moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N). The preferred method for
shifting into Four-Wheel-Drive Low is to have your
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Turn the
knob to the Four-Wheel-Drive Low position. You
must wait for the Four-Wheel-Drive Low indicator light to
stop ashing and remain on before shifting your
transmission in gear.
Notice:Shifting the transmission into gear before
the requested mode indicator light has stopped
ashing could damage the transfer case. To
help avoid damaging your vehicle, always wait for
the mode indicator lights to stop ashing before
shifting the transmission into gear.
It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting between
Four-Wheel-Drive Low and Four-Wheel-Drive High
ranges or from NEUTRAL with the engine running.
2-42

{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-49.
N (NEUTRAL):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-50orTowing
Your Vehicle on page 4-50for more information.
If the SERVICE 4–Wheel Drive message stays on, you
should take your vehicle to your dealer for service.
See “Service 4–Wheel Drive message” underDIC
Warnings and Messages on page 3-63.
Shifting Into Four-Wheel-Drive High or
AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel-Drive High or AUTO
position. This can be done at any speed, except
when shifting from Four-Wheel-Drive Low, and the
indicator light will ash while shifting. It will remain on
when the shift is completed.
Shifting Into Two-Wheel-Drive High
Turn the knob to the Two-Wheel-Drive High position.
This can be done at any speed, except when shifting
from Four-Wheel-Drive Low.
Shifting Into Four-Wheel-Drive Low
When Four-Wheel-Drive Low is engaged, vehicle speed
should be kept below 45 mph. Extended high-speed
operation in Four-Wheel-Drive Low may damage
or shorten the life of the drivetrain.
To shift to the Four-Wheel-Drive Low position, the
ignition must be in RUN and the vehicle must be
stopped or moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N). The preferred method for
shifting into Four-Wheel-Drive Low is to have your
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Turn the
knob to the Four-Wheel-Drive Low position. You
must wait for the Four-Wheel-Drive Low indicator light to
stop ashing and remain on before shifting your
transmission in gear.
2-46