
Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
2015 GMC Sierra Denali Owner ManualM
In Brief. . . . . . . . . . . . . . . . . . . . . . . . 1-1
Instrument Panel . . . . . . . . . . . . . . 1-2
Initial Drive Information . . . . . . . . 1-4
Vehicle Features . . . . . . . . . . . . . 1-16
Performance and Maintenance . . . . . . . . . . . . . . . . 1-20
Keys, Doors, and Windows . . . . . . . . . . . . . . . . . . . . 2-1
Keys and Locks . . . . . . . . . . . . . . . 2-1
Doors . . . . . . . . . . . . . . . . . . . . . . . . 2-10
Vehicle Security . . . . . . . . . . . . . . 2-11
Exterior Mirrors . . . . . . . . . . . . . . . 2-14
Interior Mirrors . . . . . . . . . . . . . . . . 2-19
Windows . . . . . . . . . . . . . . . . . . . . . 2-19
Roof . . . . . . . . . . . . . . . . . . . . . . . . . . 2-22
Seats and Restraints . . . . . . . . . 3-1
Head Restraints . . . . . . . . . . . . . . . 3-2
Front Seats . . . . . . . . . . . . . . . . . . . . 3-3
Rear Seats . . . . . . . . . . . . . . . . . . . . 3-9
Safety Belts . . . . . . . . . . . . . . . . . . 3-10
Airbag System . . . . . . . . . . . . . . . . 3-17
Child Restraints . . . . . . . . . . . . . . 3-30 Storage
. . . . . . . . . . . . . . . . . . . . . . . 4-1
Storage Compartments . . . . . . . . 4-1
Additional Storage Features . . . 4-3
Instruments and Controls . . . . 5-1
Controls . . . . . . . . . . . . . . . . . . . . . . . 5-2
Warning Lights, Gauges, and
Indicators . . . . . . . . . . . . . . . . . . . . 5-8
Information Displays . . . . . . . . . . 5-27
Vehicle Messages . . . . . . . . . . . . 5-31
Vehicle Personalization . . . . . . . 5-42
Universal Remote System . . . . 5-49
Lighting . . . . . . . . . . . . . . . . . . . . . . . 6-1
Exterior Lighting . . . . . . . . . . . . . . . 6-1
Interior Lighting . . . . . . . . . . . . . . . . 6-6
Lighting Features . . . . . . . . . . . . . . 6-8
Infotainment System . . . . . . . . . 7-1
Introduction . . . . . . . . . . . . . . . . . . . . 7-1 Climate Controls
. . . . . . . . . . . . . 8-1
Climate Control Systems . . . . . . 8-1
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 8-4
Maintenance . . . . . . . . . . . . . . . . . . . 8-5
Driving and Operating . . . . . . . . 9-1
Driving Information . . . . . . . . . . . . . 9-2
Starting and Operating . . . . . . . 9-23
Engine Exhaust . . . . . . . . . . . . . . 9-32
Automatic Transmission . . . . . . 9-33
Drive Systems . . . . . . . . . . . . . . . . 9-40
Brakes . . . . . . . . . . . . . . . . . . . . . . . 9-46
Ride Control Systems . . . . . . . . 9-49
Cruise Control . . . . . . . . . . . . . . . . 9-52
Driver Assistance Systems . . . 9-55
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 9-63
Trailer Towing . . . . . . . . . . . . . . . . 9-68
Conversions and Add-Ons . . . 9-88
Vehicle Care . . . . . . . . . . . . . . . . . 10-1
General Information . . . . . . . . . . 10-2
Vehicle Checks . . . . . . . . . . . . . . . 10-3
Headlamp Aiming . . . . . . . . . . . 10-36
Bulb Replacement . . . . . . . . . . 10-36
Electrical System . . . . . . . . . . . . 10-40
Wheels and Tires . . . . . . . . . . . 10-50

Black plate (5,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Introduction v
j:LATCH System Child
Restraints
*: Malfunction Indicator Lamp
::Oil Pressure
g:Outside Power Foldaway
Mirrors
O: Power
/:Remote Vehicle Start
>:Safety Belt Reminders
7:Tire Pressure Monitor
_: Tow/Haul Mode
d:Traction Control/StabiliTrak®
M:Windshield Washer Fluid

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
In Brief 1-1
In Brief
Instrument Panel
Instrument Panel . . . . . . . . . . . . . . 1-2
Initial Drive Information
Remote Keyless Entry (RKE)System . . . . . . . . . . . . . . . . . . . . . . 1-4
Remote Vehicle Start . . . . . . . . . 1-5
Door Locks . . . . . . . . . . . . . . . . . . . 1-5
Windows . . . . . . . . . . . . . . . . . . . . . . 1-6
Seat Adjustment . . . . . . . . . . . . . . 1-7
Memory Features . . . . . . . . . . . . . 1-8
Heated and Cooled Front Seats . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Head Restraint Adjustment . . . . 1-9
Safety Belts . . . . . . . . . . . . . . . . . . . 1-9
Passenger Sensing System . . . 1-9
Mirror Adjustment . . . . . . . . . . . . 1-10 Steering Wheel
Adjustment . . . . . . . . . . . . . . . . . 1-11
Throttle and Brake Pedal Adjustment . . . . . . . . . . . . . . . . . 1-12
Interior Lighting . . . . . . . . . . . . . . 1-12
Exterior Lighting . . . . . . . . . . . . . 1-13
Windshield Wiper/Washer . . . . 1-13
Climate Controls . . . . . . . . . . . . . 1-14
Transmission . . . . . . . . . . . . . . . . 1-15
Four-Wheel Drive . . . . . . . . . . . . 1-15
Vehicle Features
Infotainment System . . . . . . . . . 1-16
Steering Wheel Controls . . . . . 1-16
Cruise Control . . . . . . . . . . . . . . . 1-17
Driver Information Center (DIC) . . . . . . . . . . . . . . . 1-17
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . 1-18 Lane Departure
Warning (LDW) . . . . . . . . . . . . . 1-18
Rear Vision Camera (RVC) . . . . . . . . . . . . . 1-18
Parking Assist . . . . . . . . . . . . . . . 1-18
Power Outlets . . . . . . . . . . . . . . . 1-18
Universal Remote System . . . 1-19
Sunroof . . . . . . . . . . . . . . . . . . . . . . 1-19
Performance and Maintenance
Traction Control/Electronic
Stability Control . . . . . . . . . . . . 1-20
Tire Pressure Monitor . . . . . . . . 1-20
Engine Oil Life System . . . . . . 1-21
E85 or FlexFuel . . . . . . . . . . . . . . 1-21
Driving for Better Fuel Economy . . . . . . . . . . . . . . . . . . . 1-21
Roadside Assistance Program . . . . . . . . . . . . . . . . . . . . 1-22
OnStar
®. . . . . . . . . . . . . . . . . . . . . 1-22

Black plate (8,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
1-8 In Brief
.Press and hold the control up to
increase upper lumbar support
and decrease lower lumbar
support.
Press and hold the control down
to increase lower lumbar support
and decrease upper lumbar
support.
See Lumbar Adjustment on
page 3-3.
Reclining Seatbacks
To adjust the seatback:
.Tilt the top of the control
rearward to recline.
.Tilt the top of the control forward
to raise.
See Reclining Seatbacks on
page 3-4.
Memory Features
The SET, "1," "2," andB(Exit)
buttons on the driver door are used
to manually save and recall memory
settings for the driver seat, outside
mirrors, and adjustable pedals.
See Memory Seats on page 3-5 and
Vehicle Personalization on
page 5-42.
Heated and Cooled Front
Seats
The buttons are on the center stack.
To operate, the engine must be
running.

Black plate (10,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
1-10 In Brief
The passenger airbag status
indicator lights on the on the
overhead console are visible when
the vehicle is started. See
Passenger Airbag Status Indicator
on page 5-17.
Mirror Adjustment
Using hood-mounted air deflectors
and add-on convex mirror
attachments could decrease mirror
performance.
Exterior Mirrors
Power Mirrors
Base Power Mirrors
1. Press (1) or (2) to select the driver side or passenger side
mirror.
2. Press the arrows on the control pad to move the mirror up,
down, right or left.
3. Adjust each outside mirror so that a little of the vehicle and the
area behind it can be seen. Keep the selector switch in the
center position when not adjusting
either outside mirror.Uplevel with Power Folding
Mirrors
1. Press (1) or (3) to select the driver or passenger side mirror.
2. Press the arrows on the control pad to move the mirror up,
down, right, or left.
3. Adjust each outside mirror so that a little of the vehicle and the
area behind it can be seen.

Black plate (11,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
In Brief 1-11
4. Press either (1) or (3) again todeselect the mirror.
See Power Mirrors on page 2-14.
If equipped with power folding
mirrors:
1. Press (2) to fold the mirrors out to the driving position.
2. Press (2) again to fold the mirrors in to the folded position.
See Folding Mirrors on page 2-16.
The mirrors may also include a
memory function that works with the
memory seats. See Memory Seats
on page 3-5.
Interior Mirror
Adjustment
Adjust the mirror for a clear view of
the area behind the vehicle. Automatic Dimming Rearview
Mirror
The automatic dimming mirror will
automatically reduce the glare from
the headlamps from behind. The
dimming feature comes on when the
vehicle is started.
See
Automatic Dimming Rearview
Mirror on page 2-19.
Steering Wheel
Adjustment
To adjust the tilt and telescoping
steering wheel:
1. Push the lever (1) down to move
the steering wheel forward or
rearward. Lift the lever up to lock
the wheel in place.
2. Pull the lever (2) toward you and release, to move the steering
wheel up or down.
The ignition may need to be set to
the ACC/ACCESSORY or ON/RUN
position to disengage the tilt and
telescoping steering column and
allow easier adjustment.
Do not adjust the steering wheel
while driving.

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - CRC - 6/20/14
Keys, Doors, and Windows 2-1
Keys, Doors, and
Windows
Keys and Locks
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Remote Keyless Entry (RKE)System . . . . . . . . . . . . . . . . . . . . . . 2-4
Remote Keyless Entry (RKE) System Operation . . . . . . . . . . . 2-4
Remote Vehicle Start . . . . . . . . . 2-7
Door Locks . . . . . . . . . . . . . . . . . . . 2-8
Power Door Locks . . . . . . . . . . . . 2-9
Delayed Locking . . . . . . . . . . . . . . 2-9
Automatic Door Locks . . . . . . . . . 2-9
Lockout Protection . . . . . . . . . . . . 2-9
Safety Locks . . . . . . . . . . . . . . . . . . 2-9
Doors
Tailgate . . . . . . . . . . . . . . . . . . . . . . 2-10
Vehicle Security
Vehicle Security . . . . . . . . . . . . . . 2-11
Vehicle Alarm System . . . . . . . . 2-11
Immobilizer . . . . . . . . . . . . . . . . . . 2-12
Immobilizer Operation . . . . . . . 2-13
Exterior Mirrors
Convex Mirrors . . . . . . . . . . . . . . 2-14
Trailer-Tow Mirrors . . . . . . . . . . . 2-14
Power Mirrors . . . . . . . . . . . . . . . . 2-14
Folding Mirrors . . . . . . . . . . . . . . . 2-16
Heated Mirrors . . . . . . . . . . . . . . . 2-17
Automatic Dimming Mirror . . . 2-17
Blind Spot Mirrors . . . . . . . . . . . 2-17
Reverse Tilt Mirrors . . . . . . . . . . 2-18
Interior Mirrors
Interior Rearview Mirrors . . . . . 2-19
Automatic Dimming Rearview Mirror . . . . . . . . . . . . . . . . . . . . . . . 2-19
Windows
Windows . . . . . . . . . . . . . . . . . . . . . 2-19
Power Windows . . . . . . . . . . . . . 2-19
Rear Windows . . . . . . . . . . . . . . . 2-22
Sun Visors . . . . . . . . . . . . . . . . . . . 2-22
Roof
Sunroof . . . . . . . . . . . . . . . . . . . . . . 2-22
Keys and Locks
Keys
{Warning
Leaving children in a vehicle with
the ignition key is dangerous and
children or others could be
seriously injured or killed. They
could operate the power windows
or other controls or make the
vehicle move. The windows will
function with the keys in the
ignition, and children or others
could be caught in the path of a
closing window. Do not leave
children in a vehicle with the
ignition key.

Black plate (5,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - CRC - 6/20/14
Keys, Doors, and Windows 2-5
whenQis pressed again within
three seconds. See Vehicle
Personalization on page 5-42.
Pressing
Qarms the alarm system.
See Vehicle Alarm System on
page 2-11.
If equipped with auto mirror folding,
pressing and holding
Qfor
one second will fold the mirrors. The
auto mirror folding feature will not
operate unless it is enabled. See
Vehicle Personalization on
page 5-42.
K(Unlock): Press once to unlock
only the driver door. If
Kis pressed
again within three seconds, all
remaining doors unlock. The interior
lamps may come on and stay on for
20 seconds or until the ignition is
turned on.
If enabled through the DIC, the turn
signal lamps flash twice to indicate
unlocking has occurred. See Vehicle
Personalization on page 5-42.
If enabled through the DIC, the exterior lamps may turn on. See
Vehicle Personalization on
page 5-42.
If equipped, memory seat positions
may be recalled when unlocking the
vehicle if enabled. See
Vehicle
Personalization on page 5-42 and
Memory Seats on page 3-5.
Pressing
Kon the RKE transmitter
disarms the alarm system. See
Vehicle Alarm System on page 2-11.
If equipped with auto mirror folding,
pressing and holding
Kfor
one second will unfold the mirrors.
The auto mirror folding feature will
not operate unless it is enabled.
See Vehicle Personalization on
page 5-42.
On some models, press, release
and then press and hold
Kto open
all of the windows. Pressing the
button again will stop the windows.
7(Vehicle Locator/Panic
Alarm): Press and release one
time to initiate vehicle locator. The
turn signal lamps flash and the horn
sounds three times.
Press and hold
7for at least
three seconds to sound the panic
alarm. The turn signal lamps flash
and the horn sounds repeatedly for
30 seconds. The alarm turns off
when the ignition is moved to ON/
RUN or
7is pressed again. The
ignition must be in LOCK/OFF for
the panic alarm to work.
Programming Transmitters to
the Vehicle
Only RKE transmitters programmed
to this vehicle will work. If a
transmitter is lost or stolen, a
replacement can be purchased and
programmed through your dealer.
Each vehicle can have up to
eight transmitters programmed to it.
See your dealer for transmitter
programming.