
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
In Brief 5
In Brief Instrument Panel Instrument Panel . . . . . . . . . . . . . . . . 6
Initial Drive Information Initial Drive Information . . . . . . . . . . 8
Remote Keyless Entry (RKE)
System . . . . . . . . . . . . . . . . . . . . . . . . 8
Remote Vehicle Start . . . . . . . . . . . 9
Door Locks . . . . . . . . . . . . . . . . . . . . . 9
Windows . . . . . . . . . . . . . . . . . . . . . . . 10
Seat Adjustment . . . . . . . . . . . . . . . 11
Memory Features . . . . . . . . . . . . . . 13
Heated and Ventilated Seats . . . 13
Head Restraint Adjustment . . . . 14
Seat Belts . . . . . . . . . . . . . . . . . . . . . 14
Passenger Sensing System . . . 14
Mirror Adjustment . . . . . . . . . . . . . . 15
Steering Wheel Adjustment . . . . 16
Throttle and Brake Pedal
Adjustment . . . . . . . . . . . . . . . . . . . 17
Interior Lighting . . . . . . . . . . . . . . . . 17
Exterior Lighting . . . . . . . . . . . . . . . 18
Windshield Wiper/Washer . . . . . . 19
Climate Controls . . . . . . . . . . . . . . . 20
Transmission . . . . . . . . . . . . . . . . . . 22
Four-Wheel Drive . . . . . . . . . . . . . . 23 Vehicle Features Infotainment System . . . . . . . . . . . 24
Radio(s) . . . . . . . . . . . . . . . . . . . . . . . 24
Satellite Radio . . . . . . . . . . . . . . . . . 25
Portable Audio Devices . . . . . . . . 25
Bluetooth . . . . . . . . . . . . . . . . . . . . . . 25
Steering Wheel Controls . . . . . . . 26
Cruise Control . . . . . . . . . . . . . . . . . 26
Driver Information
Center (DIC) . . . . . . . . . . . . . . . . . 27
Forward Collision Alert (FCA)
System . . . . . . . . . . . . . . . . . . . . . . . 27
Forward Automatic
Braking (FAB) . . . . . . . . . . . . . . . . 27
Lane Departure
Warning (LDW) . . . . . . . . . . . . . . . 28
Lane Keep Assist (LKA) . . . . . . . 28
Rear Vision Camera (RVC) . . . . 28
Parking Assist . . . . . . . . . . . . . . . . . 28
Power Outlets . . . . . . . . . . . . . . . . . 28
Universal Remote System . . . . . 29
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . 29
Performance and Maintenance Traction Control/Electronic
Stability Control . . . . . . . . . . . . . . 30
Tire Pressure Monitor . . . . . . . . . . 31
Fuel (Gasoline - Except
L86 6.2L Engine) . . . . . . . . . . . . . 31 Fuel (Gasoline - L86 6.2L
Engine) . . . . . . . . . . . . . . . . . . . . . . . 32
Fuel (Diesel) . . . . . . . . . . . . . . . . . . . 32
E85 or FlexFuel . . . . . . . . . . . . . . . . 32
Engine Oil Life System . . . . . . . . 32
Driving for Better Fuel
Economy . . . . . . . . . . . . . . . . . . . . . 33
Roadside Assistance
Program . . . . . . . . . . . . . . . . . . . . . . 33 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
In Brief 11
Seat Adjustment Manual Seats
To adjust a manual seat:
1. Pull the handle at the front of
the seat.
2. Slide the seat to the desired
position and release the
handle.
3. Try to move the seat back and
forth to be sure it is locked in
place.
See Seat Adjustment 0 59 . Power Seats
To adjust a power seat, if equipped:
.
Move the seat forward or
rearward by sliding the control
forward or rearward.
.
If equipped, raise or lower the
front part of the seat cushion by
moving the front of the control
up or down.
.
If equipped, raise or lower the
seat by moving the rear of the
control up or down.
See Power Seat Adjustment 0 60 .Lumbar Adjustment Manual Lumbar
If equipped, move the lever up or
down repeatedly to increase or
decrease lumbar support.
See Lumbar Adjustment 0 60 . 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
12 In Brief Power Lumbar
To adjust the power lumbar support,
if equipped:
.
Press and hold the control
forward to increase or rearward
to decrease upper and lower
lumbar support at the same time.
.
If equipped, 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 0 60 .
Reclining Seatbacks Manual Reclining Seatbacks
To adjust a manual seatback:
1. Lift the lever.
The seatback will automatically
fold forward.
2. To recline, move the seatback
rearward to the desired
position, then release the lever
to lock the seatback in place.
3. Push and pull on the seatback
to make sure it is locked. To return the seatback to the upright
position:
1. Lift the lever fully without
applying pressure to the
seatback, and the seatback will
return to the upright position.
2. Push and pull on the seatback
to make sure it is locked.
See Reclining Seatbacks 0 61 .
Power Reclining Seatbacks
To recline a power seatback,
if equipped:
.
Tilt the top of the control
rearward to recline. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
14 In Brief Press
C to ventilate the driver or
passenger seat.
See Heated and Ventilated Front
Seats 0 65 .
Head Restraint
Adjustment Do not drive until the head restraints
for all occupants are installed and
adjusted properly.
To achieve a comfortable seating
position, change the seatback
recline angle as little as necessary
while keeping the seat and the head
restraint height in the proper
position.
See Head Restraints 0 58 and
Power Seat Adjustment 0 60 .Seat Belts
Refer to the following sections for
important information on how to use
seat belts properly:
.
Seat Belts 0 69 .
.
How to Wear Seat Belts Properly
0 70 .
.
Lap-Shoulder Belt 0 71 .
.
Lower Anchors and Tethers for
Children (LATCH System) 0 99 .Passenger Sensing
System The passenger sensing system,
if equipped, turns off the front
outboard passenger frontal airbag
under certain conditions. No other
airbag is affected by the passenger
sensing system.
If the vehicle has one of the
indicators pictured in the following
illustrations, then the vehicle has a
passenger sensing system for the
front outboard passenger position
unless there is an airbag off switch
on the instrument panel endcap.
If there is an airbag off switch, the
vehicle does not have a passenger
sensing system. See Airbag On-Off
Switch 0 84 for more information.
The passenger airbag status
indicator will be visible on the
overhead console when the vehicle
is started. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
16 In Brief 2. Press the arrows on the control
pad while the indicator light on
the (1) or (3) button is
illuminated, 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.
4. Press either (1) or (3) again to
deselect the mirror.
See Power Mirrors 0 48 .
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.
For manual, power, and auto folding
mirrors, see Folding Mirrors 0 49 .
The mirrors may also include a
memory function that works with the
memory seats. See Memory Seats
0 62 . Interior Mirror Adjustment
Adjust the mirror for a clear view of
the area behind the vehicle.
Manual Dimming Rearview Mirror
If equipped, push the tab forward for
daytime use and pull it for nighttime
use to avoid glare from the
headlamps from behind. See
Manual Rearview Mirror 0 52 .
Automatic Dimming Rearview
Mirror
If equipped, the mirror will
automatically reduce the glare of the
headlamps from behind. The
dimming feature comes on when the
vehicle is started.
See Automatic Dimming Rearview
Mirror 0 52 . Steering Wheel
Adjustment
To adjust the steering wheel:
1. Hold the steering wheel and
pull the lever.
2. Move the steering wheel up
or down.
3. Release the lever to lock the
wheel in place. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 57
Seats and
Restraints Head Restraints Head Restraints . . . . . . . . . . . . . . . 58
Front Seats Seat Adjustment . . . . . . . . . . . . . . . 59
Center Seat . . . . . . . . . . . . . . . . . . . . 59
Power Seat Adjustment . . . . . . . . 60
Lumbar Adjustment . . . . . . . . . . . . 60
Reclining Seatbacks . . . . . . . . . . . 61
Memory Seats . . . . . . . . . . . . . . . . . 62
Heated and Ventilated Front
Seats . . . . . . . . . . . . . . . . . . . . . . . . . 65
Rear Seats Rear Seats (Double Cab Full
Bench) . . . . . . . . . . . . . . . . . . . . . . . 66
Rear Seats (Split Bench) . . . . . . 68
Seat Belts Seat Belts . . . . . . . . . . . . . . . . . . . . . 69
How to Wear Seat Belts
Properly . . . . . . . . . . . . . . . . . . . . . . 70
Lap-Shoulder Belt . . . . . . . . . . . . . 71
Seat Belt Use During
Pregnancy . . . . . . . . . . . . . . . . . . . . 74
Lap Belt . . . . . . . . . . . . . . . . . . . . . . . 75 Seat Belt Extender . . . . . . . . . . . . . 75
Safety System Check . . . . . . . . . . 75
Seat Belt Care . . . . . . . . . . . . . . . . . 76
Replacing Seat Belt System
Parts after a Crash . . . . . . . . . . . 76
Airbag System Airbag System . . . . . . . . . . . . . . . . . 77
Where Are the Airbags? . . . . . . . 78
When Should an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . . 80
What Makes an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . . 82
How Does an Airbag
Restrain? . . . . . . . . . . . . . . . . . . . . . 82
What Will You See after an
Airbag Inflates? . . . . . . . . . . . . . . 82
Airbag On-Off Switch . . . . . . . . . . 84
Passenger Sensing System . . . 86
Servicing the Airbag-Equipped
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 90
Adding Equipment to the
Airbag-Equipped Vehicle . . . . . 90
Airbag System Check . . . . . . . . . . 91
Replacing Airbag System Parts
after a Crash . . . . . . . . . . . . . . . . . 92
Child Restraints
Older Children . . . . . . . . . . . . . . . . . 92
Infants and Young Children . . . . 94
Child Restraint Systems . . . . . . . 96 Where to Put the Restraint . . . . . 98
Lower Anchors and Tethers for
Children (LATCH System) . . . . 99
Replacing LATCH System
Parts After a Crash . . . . . . . . . . 111
Securing Child Restraints (With
the Seat Belt in the
Rear Seat) . . . . . . . . . . . . . . . . . . 111
Securing Child Restraints (With
the Seat Belt in the Center
Front Seat) . . . . . . . . . . . . . . . . . . 114
Securing Child Restraints (With
the Seat Belt in the Front
Passenger Seat) . . . . . . . . . . . . 115 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 59Rear Seats The rear seat has adjustable
headrests in the outboard seating
positions.
The height of the headrest can be
adjusted. Pull the headrest up to
raise it. To lower the headrest, push
the headrest down.
If you are installing a child restraint
in the rear seat, see “ Securing a
Child Restraint Designed for the
LATCH System ” under Lower
Anchors and Tethers for Children
(LATCH System) 0 99 .Front Seats Seat Adjustment
{ WarningYou can lose control of the
vehicle if you try to adjust a driver
seat while the vehicle is moving.
Adjust the driver seat only when
the vehicle is not moving.
To adjust a manual seat:
1. Pull the handle at the front of
the seat. 2. Slide the seat to the desired
position and release the
handle.
3. Try to move the seat back and
forth to be sure it is locked in
place.
To adjust the seatback, see
Reclining Seatbacks 0 61 .
To adjust the lumbar support,
if equipped, see Lumbar Adjustment
0 60 .
Center Seat If equipped, the center front
seatback doubles as an armrest and
cupholder/storage area for the driver
and passenger when the center
front seat is not used. Do not use it
as a seating position when the
seatback is folded down. 

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
60 Seats and Restraints
Power Seat Adjustment
To adjust a power seat, if equipped:
.
Move the seat forward or
rearward by sliding the control
forward or rearward.
.
If equipped, raise or lower the
front part of the seat cushion by
moving the front of the control
up or down.
.
If equipped, raise or lower the
seat by moving the rear of the
control up or down.
To adjust the seatback, see
Reclining Seatbacks 0 61 . To adjust the lumbar support, see
Lumbar Adjustment 0 60 .
Some vehicles are equipped with a
feature that activates a vibrating
pulse alert in the driver seat to help
the driver avoid crashes. See Driver
Assistance Systems 0 288 .
Lumbar Adjustment Manual Lumbar
If equipped, move the lever up or
down repeatedly to increase or
decrease lumbar support. Power Lumbar
To adjust the power lumbar support,
if equipped:
.
Press and hold the control
forward to increase or rearward
to decrease upper and lower
lumbar support at the same time.
.
If equipped, 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.