
Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-6
Safety Belts
.............................................. 1-7
Child Restraints
.......................................1-29
Air Bag Systems
......................................1-55
Restraint System Check
............................1-71
Features and Controls..................................... 2-1
Keys
........................................................ 2-2
Doors and Locks
....................................... 2-6
Windows
.................................................2-11
Theft-Deterrent Systems
............................2-13
Starting and Operating Your Vehicle
...........2-15
Mirrors
....................................................2-28
OnStar
®System
......................................2-33
HomeLink®Transmitter
.............................2-35
Storage Areas
.........................................2-39
Vehicle Personalization
.............................2-41
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-2
Climate Controls
......................................3-18
Warning Lights, Gages and Indicators
.........3-24
Driver Information Center (DIC)
..................3-42
Audio System(s)
.......................................3-56Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-46
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
Checking Things Under
the Hood
.............................................5-10
All-Wheel Drive
........................................5-45
Rear Axle
...............................................5-46
Front Axle
...............................................5-47
Bulb Replacement
....................................5-48
Windshield Wiper Blade Replacement
.........5-56
Tires
......................................................5-56
Appearance Care
.....................................5-82
Vehicle Identi cation
.................................5-90
Electrical System
......................................5-91
Capacities and Speci cations
.....................5-99
Normal Maintenance Replacement Parts
....5-100
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance Information
.................. 7-2
Reporting Safety Defects
............................ 7-8
Index................................................................ 1
2003 GMC Sierra Denali Owner ManualM
2003 - Sierra Denali Owner Manual 

Keys...............................................................2-2
Remote Keyless Entry System.........................2-3
Remote Keyless Entry System Operation...........2-4
Doors and Locks.............................................2-6
Door Locks....................................................2-6
Power Door Locks..........................................2-7
Programmable Automatic
Door Locks................................................2-7
Rear Doors...................................................2-9
Tailgate.......................................................2-10
Windows........................................................2-11
Power Windows............................................2-12
Swing-Out Windows......................................2-12
Sun Visors...................................................2-13
Theft-Deterrent Systems..................................2-13
Content Theft-Deterrent.................................2-13
Passlock
®....................................................2-15
Starting and Operating Your Vehicle................2-15
New Vehicle Break-In....................................2-15
Ignition Positions
..........................................2-16
Starting Your Engine
.....................................2-17
Engine Coolant Heater
..................................2-18
Automatic Transmission Operation
...................2-19
All-Wheel Drive
............................................2-21
Parking Brake
..............................................2-22Shifting Into Park (P).....................................2-23
Shifting Out of Park (P).................................2-25
Parking Over Things That Burn.......................2-26
Engine Exhaust............................................2-26
Running Your Engine While You Are Parked. . . .2-27
Mirrors...........................................................2-28
Automatic Dimming Rearview Mirror with
OnStar
®, Compass and Temperature
Display....................................................2-28
Outside Power Mirrors...................................2-31
Outside Power Foldaway Mirrors.....................2-31
Outside Automatic Dimming Mirror..................2-32
Outside Curb View Assist Mirrors....................2-32
Outside Convex Mirror...................................2-32
Outside Heated Mirrors..................................2-32
OnStar
®System.............................................2-33
HomeLink®Transmitter...................................2-35
Programming the HomeLink®Transmitter.........2-35
Storage Areas................................................2-39
Glove Box...................................................2-39
Cupholder(s)................................................2-39
Center Console Storage Area.........................2-39
Tonneau Cover............................................2-39
Vehicle Personalization...................................2-41
Memory Seat...............................................2-41
Section 2 Features and Controls
2-1
2003 - Sierra Denali 

Your vehicle has one
double-sided key for the
ignition and all door
locks as well as the spare
tire hoist lock, if equipped.
If you ever lose your keys, your dealer will be able to
assist you with obtaining replacements.
Notice:Your vehicle has a number of features that
can help prevent theft. You can have a lot of
trouble getting into your vehicle if you ever lock
your keys inside. You may even have to damage
your vehicle to get in. So be sure you have
spare keys.
If you ever do get locked out of your vehicle, call the
GM Roadside Assistance Center. SeeRoadside
Assistance Program on page 7-5. If your vehicle is
equipped with the OnStar
®system with an active
subscription and you lock your keys inside the vehicle,OnStar
®may be able to send a command to unlock
your vehicle. SeeOnStar®System on page 2-33
for more information.
Remote Keyless Entry System
Your keyless entry system operates on a radio
frequency subject to Federal Communications
Commission (FCC) Rules and with Industry Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause interference, and
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference, and
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modi cations to this system by other than
an authorized service facility could void authorization to
use this equipment.
2-3
2003 - Sierra Denali 

Mirrors
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, an
electrochromic mirror automatically dims to the proper
level to minimize glare from lights behind you after dark.
The mirror also includes a duel 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.
Temperature and Compass Display
Press the on/off button, located to the far left, brie yto
turn the comp/temp display on or off.
If the display reads CAL, you will need to calibrate the
compass. For more information on calibration, see
below.
To adjust between Fahrenheit and Celsius do the
following:
1. Press and hold the on/off button for approximately
four seconds until either a ashing°F, or°C
appears.
2. Press the button again to change the display to the
desired unit of measurement. After approximately
four seconds of inactivity, the new unit will be locked
in and the compass/temperature display will
return.
Electrochromic Mirror Operation
The electrochromic (self dimming) mirror function is
turned on automatically each time the ignition is started.
To operate the electrochromic mirror do the following:
1. Make sure the green indicator light, located to
the left of the on/off button, is lit. If it’s not, press
and hold the on/off button for approximately
six seconds until the green light comes on,
indicating that the mirror is in electrochromic
(self dimming) mode.
2-28
2003 - Sierra Denali 

Outside Automatic Dimming Mirror
The driver’s outside mirror will adjust for the glare of any
headlamps behind you. This feature is controlled by
the on and off settings on the electrochromic mirror.
See“Electrochromic Mirror Operation”underAutomatic
Dimming Rearview Mirror with OnStar
®, Compass
and Temperature Display on page 2-28.
Outside Curb View Assist Mirrors
If your vehicle has the optional memory package
you may have this feature.
The vehicle’s mirrors are capable of performing the curb
view assist mirror function. This feature will cause the
passenger’s and/or driver’s mirror to tilt to a preselected
position when the vehicle is in REVERSE (R). This
feature may be useful in allowing you to view the curb
when you are parallel parking. When the vehicle is
shifted out of REVERSE (R) and a short delay
has occurred, the passenger’s and/or driver’s mirror will
return to its original position.
To change the preselected tilt position, adjust the
mirrors to the desired position while the vehicle is in
REVERSE (R). When the vehicle is shifted out of
REVERSE (R), this new position is saved in memory as
the tilt position.
You may be able to enabled/disable this feature through
the Driver Information Center. SeeDriver Information
Center (DIC) on page 3-42.
Outside Convex Mirror
Your passenger’s side mirror is convex. A convex
mirror’s surface is curved so you can see more from the
driver’s seat.
{CAUTION:
A convex mirror can make things (like other
vehicles) look farther away than they really are.
If you cut too sharply into the right lane, you
could hit a vehicle on your right. Check your
inside mirror or glance over your shoulder
before changing lanes.
Outside Heated Mirrors
The outside rearview mirrors with this option have a
defrost mode.
To turn on the defrost feature, press the rear window
defogger button. See“Rear Window Defogger”
underDual Automatic Climate Control System on
page 3-18for further information.
2-32
2003 - Sierra Denali 

OnStar®System
OnStar®uses global positioning system (GPS) satellite
technology, wireless communications, and state of
the art call centers to provide you with a wide range of
safety, security, information and convenience services.
An OnStar
®subscription plan is included in the price
of your vehicle. You can easily upgrade or extend your
OnStar
®services to meet your personal needs.
A complete OnStar
®user’s guide and the terms and
conditions of the OnStar®Subscription Service
Agreement are included in your OnStar®-equipped
vehicle’s glove box literature. For more information, visit
www.onstar.com, contact OnStar
®at 1−888−4−ONSTAR
(1−888−466−7827), or press the blue OnStar®button to
speak to an OnStar®advisor 24 hours a day, 7 days
a week.
OnStar®Services
OnStar®provides a number of service plans to closely
meet your needs. Some of the services currently
provided by OnStar
®are:
Automatic Noti cation of Air Bag Deployment
Emergency Services
Roadside Assistance Stolen Vehicle Tracking
AccidentAssist
Remote Door Unlock
Remote Diagnostics
Online and Personal Concierge Services
Route Support
RideAssist
Information and Convenience Services
2-33
2003 - Sierra Denali 

OnStar®Personal Calling
With OnStar®Personal Calling, you have a safer way to
stay connected while driving. It’s a hands-free wireless
phone that’s integrated into your vehicle. You can place
calls nationwide using voice-activated dialing with no
contracts, no roaming charges and no access fees.
To nd out more about OnStar
®Personal Calling, refer
to the OnStar®owner’s guide in your vehicle’s glove
box, or call OnStar®at 1−888−4−ONSTAR
(1−888−466−7827).
OnStar®Virtual Advisor
With OnStar®Virtual Advisor you can listen to your
favorite news, entertainment and information topics,
such as traffic and weather reports, stock quotes
and sports scores. You listen to your e-mail through
your vehicle’s speakers, and reply with your hands on
the wheel and your eyes on the road.
A completed Subscription Service Agreement is required
prior to delivery of OnStar
®services and prepaid
calling minutes are also required for OnStar®Personal
Calling and OnStar®Virtual Advisor use. Terms and
conditions of the Subscription Service Agreement can be
found at www.onstar.com.
OnStar®Steering Wheel Controls
g
: If your vehicle is
equipped with the steering
wheel control buttons
you can use them
to interact with the OnStar
®
system.
See the OnStar
®manual provided with your vehicle for
more information.
2-34
2003 - Sierra Denali 

Audio Steering Wheel Controls
You can control certain radio functions using the buttons
on your steering wheel.
g(OnStar/Voice Recognition):If your vehicle has
OnStar®, you can press this button to interact with
the OnStar®system. See the OnStar®manual provided
with your vehicle for more information.
IF your vehicle does not have OnStar
®, pressing this
button will mute the audio system.
PROG (Program):Press this button to play a station
you have programmed on the radio preset pushbuttons
on the selected band. If a cassette tape is playing,
press this button to play the other side of the tape. If a
CD is playing, press this button to go to the next
available CD.
QSOURCER:Press this button to select AM, FM1,
FM2, or XM1 or XM2, (USA only, if equipped), or a
cassette tape or CD. The cassette or CD must be loaded
to play. Available loaded sources are shown on the
display as a tape or a CD symbol.
QSEEKR:Press the up or the down arrow to seek
to the next or to the previous radio station and stay
there.
QVOLR:Press the up or the down arrow to increase
or to decrease volume.
Understanding Radio Reception
AM
The range for most AM stations is greater than for FM,
especially at night. The longer range, however, can
cause stations to interfere with each other. AM can pick
up noise from things like storms and power lines. Try
reducing the treble to reduce this noise if you ever get it.
FM Stereo
FM stereo will give you the best sound, but FM signals
will reach only about 10 to 40 miles (16 to 65 km).
Tall buildings or hills can interfere with FM signals,
causing the sound to come and go.
3-76
2003 - Sierra Denali