
Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-3
Rear Seats
............................................... 1-9
Safety Belts
.............................................1-11
Child Restraints
.......................................1-33
Airbag System
.........................................1-66
Restraint System Check
............................1-82
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
....................................... 2-8
Windows
.................................................2-16
Theft-Deterrent Systems
............................2-19
Starting and Operating Your Vehicle
...........2-21
Mirrors
....................................................2-55
OnStar
®System
......................................2-64
HomeLink®Transmitter
.............................2-66
Storage Areas
.........................................2-70
Sunroof
..................................................2-73
Vehicle Personalization
.............................2-74
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-21
Warning Lights, Gages, and Indicators
........3-31
Driver Information Center (DIC)
..................3-50
Audio System(s)
.......................................3-69Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
........ 4-2
Towing
...................................................4-62
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-4
Fuel
......................................................... 5-6
Checking Things Under the Hood
...............5-12
Rear Axle
...............................................5-58
Four-Wheel Drive
.....................................5-58
Front Axle
...............................................5-60
Noise Control System
...............................5-61
Bulb Replacement
....................................5-62
Windshield Wiper Blade Replacement
.........5-72
Tires
......................................................5-72
Appearance Care
...................................5-112
Vehicle Identi cation
...............................5-120
Electrical System
....................................5-121
Capacities and Speci cations
...................5-130
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance and Information.............. 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-10
Index................................................................ 1
2005 GMC Sierra Owner ManualM

6. To tighten the belt, push down on the child restraint,
pull the shoulder portion of the belt to tighten the
lap portion of the belt and feed the shoulder
belt back into the retractor. If you are using a
forward-facing child restraint, you may nd it helpful
to use your knee to push down on the child
restraint as you tighten the belt. You should not be
able to pull more of the belt from the retractor
once the lock has been set.
7. Push and pull the child restraint in different
directions to be sure it is secure.8. If the airbag is off, the off indicator in the inside
rearview mirror will be lit and stay lit when the
key is turned to RUN or START.
If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child restraint.
If after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, check to make
sure that the vehicle’s seatback is not pressing the child
restraint into the seat cushion. If this happens, slightly
recline the vehicle’s seatback and adjust the seat
cushion if possible. Also make sure the child restraint is
not trapped under the vehicle head restraint. If this
happens, adjust the head restraint.
If the on indicator is still lit, secure the child in the child
restraint in a rear seat position in the vehicle and
check with your dealer.
To remove the child restraint, just unbuckle the vehicle’s
safety belt and let it go back all the way. The safety
belt will move freely again and be ready to work for an
adult or larger child passenger.
1-65

The airbag system is designed to work properly under a
wide range of conditions, including off-road usage.
Observe safe driving speeds, especially on rough
terrain. As always, wear your safety belt. SeeOff-Road
Driving with Your Four-Wheel-Drive Vehicle on
page 4-20for more tips on off-road driving.
Single Stage vs. Dual Stage Airbags
Depending on the weight of your vehicle you will have
either “Single Stage Airbags” or “Dual Stage Airbags”.
Vehicles that have a passenger sensing system
also have dual stage airbags. If the rearview mirror in
your vehicle has a passenger airbag status indicator
printed on it, your vehicle has the passenger sensing
system and therefore, it has dual stage airbags. If
the rearview mirror in your vehicle does not have a
passenger airbag status indicator printed on it, then your
vehicle does not have the passenger sensing system
and it has single stage airbags. SeePassenger
Airbag Status Indicator on page 3-36orPassenger
Sensing System on page 1-76.
Dual Stage Airbags
If your vehicle has frontal airbags with dual stage
deployment, the amount of restraint will adjust according
to crash severity. Your vehicle is equipped with electronic
frontal sensors which help the sensing system distinguish
between a moderate and a more severe frontal impact.
For moderate frontal impacts, these airbags in ate at a
level less than full deployment. For more severe frontal
impacts, full deployment occurs. If the front of your
vehicle goes straight into a wall that does not move or
deform, the threshold level for the reduced deployment is
about 10 to 16 mph (16 to 25 km/h), and the threshold
level for a full deployment is about 20 to 25 mph
(32 to 40 km/h). (The threshold level can vary, however,
with speci c vehicle design, so that it can be somewhat
above or below this range.)
Vehicle’s with dual stage airbags are also equipped with
special sensors which enable the sensing system to
monitor the position of both the driver and passenger
front seats. The seat position sensor provides
information which is used to determine if the airbags
should deploy at a reduced level or at full deployment.
1-70

To turn the right front passenger’s airbag on again,
insert your ignition key into the switch, push in,
and move the switch to the on position.
Passenger Sensing System
If your rearview mirror has one of the indicators pictured
in the following illustrations, your vehicle has a passenger
sensing system. The indicator will be visible when you
turn your ignition key to RUN or START. The words ON
and OFF or the symbol for on and off, will be visible on
the rearview mirror during the system check. When the
system check is complete, either the word ON or the word
OFF, or the symbol for on or the symbol for off will be
visible. SeePassenger Airbag Status Indicator onpage 3-36. If your rearview mirror does not have either of
the indicators pictured below, then your vehicle does not
have the passenger sensing system.
The passenger sensing system will turn off the right
front passenger’s frontal airbag under certain conditions.
The driver’s airbag is not part of the passenger
sensing system. United States
Canada
Passenger Airbag Status Indicator – United States
Passenger Airbag Status Indicator−Canada
1-76

Adding Equipment to Your
Airbag-Equipped Vehicle
Q:Is there anything I might add to the front of the
vehicle that could keep the airbags from
working properly?
A:Yes. If you add things that change your vehicle’s
frame, bumper system, front end sheet metal or
height, they may keep the airbag system from
working properly. Also, the airbag system may not
work properly if you relocate any of the airbag
sensors. If you have any questions about this, you
should contact Customer Assistance before you
modify your vehicle. The phone numbers and
addresses for Customer Assistance are in Step Two
of the Customer Satisfaction Procedure in this
manual. SeeCustomer Satisfaction Procedure on
page 7-2
Q:What if I added a snow plow? Will it keep the
airbags from working properly?
A:We have designed our airbag systems to work
properly under a wide range of conditions, including
snow plowing with vehicles equipped with the
optional Snow Plow Prep Package (RPO VYU). But
do not change or defeat the snow plow’s “tripping
mechanism.” If you do, it can damage your snow
plow and your vehicle, and it may cause an airbag
in ation.
Q:Because I have a disability, I have to get my
vehicle modi ed. How can I nd out whether
this will affect my advanced airbag system?
A:Changing or moving any parts of the front seats,
safety belts, the airbag sensing and diagnostic
module (located under the driver’s seat), or
the inside rearview mirror can affect the operation
of the advanced airbag system. If you have
questions, call Customer Assistance. The phone
numbers and addresses for Customer Assistance
are in Step Two of the Customer Satisfaction
Procedure in this manual. SeeCustomer
Satisfaction Procedure on page 7-2.
1-81

Keys...............................................................2-3
Remote Keyless Entry System.........................2-4
Remote Keyless Entry System Operation...........2-5
Doors and Locks.............................................2-8
Door Locks....................................................2-8
Power Door Locks..........................................2-9
Delayed Locking...........................................2-10
Programmable Automatic Door Locks..............2-10
Rear Door Security Locks (Crew Cab).............2-13
Lockout Protection........................................2-13
Rear Doors..................................................2-14
Tailgate.......................................................2-15
Windows........................................................2-16
Manual Windows..........................................2-16
Power Windows............................................2-17
Swing-Out Windows......................................2-18
Sliding Rear Window.....................................2-18
Sun Visors...................................................2-18
Theft-Deterrent Systems..................................2-19
Content Theft-Deterrent.................................2-19
Passlock
®....................................................2-21
Starting and Operating Your Vehicle................2-21
New Vehicle Break-In....................................2-21
Ignition Positions..........................................2-22
Retained Accessory Power (RAP)...................2-23Starting Your Engine.....................................2-23
Engine Coolant Heater..................................2-25
Automatic Transmission Operation...................2-26
Tow/Haul Mode............................................2-29
Manual Transmission Operation......................2-32
Four-Wheel Drive..........................................2-37
Parking Brake..............................................2-48
Shifting Into Park (P)
(Automatic Transmission)............................2-49
Shifting Out of Park (P)
(Automatic Transmission)............................2-51
Parking Your Vehicle
(Manual Transmission)...............................2-52
Parking Over Things That Burn.......................2-52
Engine Exhaust............................................2-53
Running Your Engine While You Are 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..............2-58
Outside Manual Mirrors..................................2-60
Outside Camper-Type Mirrors.........................2-61
Outside West Coast-Type Mirrors....................2-61
Section 2 Features and Controls
2-1

{CAUTION:
Four-wheel drive vehicles with the transfer
case in NEUTRAL will allow the vehicle to roll,
even if your automatic transmission shift lever
is in PARK (P). So, be sure the transfer case is
in a drive gear — not in NEUTRAL. Always set
your parking brake.
Follow the proper steps to be sure your vehicle will not
move. SeeShifting Into Park (P) (Automatic
Transmission) on page 2-49.
If you are pulling a trailer, seeTowing a Trailer on
page 4-68.
Mirrors
Manual Rearview Mirror
Pull or push the tab under the mirror to adust it to the
night or daytime setting. In the nightime setting, the glare
from headlamps behind the vehicle will be less intense.
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, an
automatic dimming mirror automatically dims to the
proper level to minimize glare from lights behind
you after dark.
The mirror also includes a dual display in the upper
right corner of the mirror face. The compass reading and
the outside temperature will both appear in the display
at the same time.
P(On/Off):This is the on/off button.
2-55

Passenger Airbag Indicator
The vehicle may be equipped with a passenger airbag
indicator, on the mirror glass, just above the buttons.
If the vehicle has this feature, the mirror will display the
word ON, or an airbag symbol in Canada, when the
passenger airbag is enabled. For more information, see
Passenger Sensing System on page 1-76.
Cleaning the Mirror
When cleaning the mirror, use a paper towel or similar
material dampened with glass cleaner. Do not spray
glass cleaner directly on the mirror as that may cause
the liquid cleaner to enter the mirror housing.
Automatic Dimming Rearview Mirror
with Compass and Temperature
Display
If the vehicle is equipped with an automatic mirror, it
will, when on, automatically dim to the proper level
to minimize glare from lights behind you after dark.
The mirror also includes a display in the upper
right corner of the mirror face. The compass reading
and the outside temperature will both appear in
the display at the same time. The dual display can be
turned on or off by brie y pressing either the TEMP
or the COMP button.
Temperature Display
The temperature can be displayed by pressing the
TEMP button. Pressing the TEMP button once brie y,
will toggle the temperature reading on and off. To
alternate the temperature reading between Fahrenheit
and Celsius, press and hold the TEMP button for
approximately four seconds until the display blinks F
and C. Press and release the TEMP button to toggle
between the Fahrenheit and Celsius readings. After
approximately four seconds of inactivity, the display will
stop blinking and display the last selection made.
If an abnormal reading is displayed, for an extended
period of time, please consult your dealer. Under certain
circumstances, a delay in updating the temperature is
normal.
Automatic Dimming Mirror Operation
The time period you need to press and hold the TEMP
button to turn the automatic dimming feature on or
off is approximately eight seconds. The indicator light to
the left of the TEMP button will still turn on or off to
show you when the automatic dimming feature is
activated. Once the mirror is turned off, it will remain off
until it is turned back on, or until the vehicle is
restarted.
2-58