2021 GMC SIERRA trailer

3
Read your Owner’s Manual to
learn about the information being
relayed by the lights, gauges and
indicators on the instrument cluster.

See Introduction in your
Owner’s Manual.
Driver’s Heated/ Ventilated Seat Buttons
F
Infotainment
System (8-inch* screen shown
F) Passenger’s Heated/
Ventilated Seat ButtonsF
Infotainment System
Controls Climate
Controls
F
USB Ports/
Accessory Power Outlet/120-Volt Power Outlet
F
Integrated
Trailer Brake Control
F
Wireless
Charging Pad
F
Lane Keep AssistF/
Park AssistF/Auto Engine
Stop-Start Disable/Power Release Tailgate
F/
Hazard Warning Flashers Buttons
F Optional equipment *Screen measured diagonally
Traction Control-StabiliTrak Off/
Power Outlet
F/Hill
Descent ControlF/
Power WindowsF/
MultiPro Power Assist Steps
F Buttons
Vehicle Ahead
Antilock Brake System
Low Tire Pressure
Door Ajar
Charging System
Driver Seat Belt Reminder
2 Passenger Seat Belt
Reminder

AU TO 4WD Mode

16F Optional equipment required
CAMERA SYSTEM FEATURES
The available camera systems feature up to 8 camerasF with up to 15 viewsF to help
make it easier to hitch a trailer and provide better visibility while towing.
REAR VISION CAMERA
When the vehicle is in Reverse, a view of the area behind the vehicle dis plays on the infotainment screen. Camera view buttonsF are on the screen.
Touch the Guidance Lines or Hitch Guid ance button to change gu idelines.
Touch the Hitch View button for a zoomed-in view of the hitch area.
SURROUND VISIONF
High-definition rear, front or side c amera views along with a view of the area surrounding the
vehicle are displayed on the infotainment screen
when the vehicle is in Reverse or Drive. Camera
view buttonsF are on the screen.
Touch the Guidance Lines or
Hitch Guidance button to change guidelines.
Touch the Bed View button to view the
bed to check cargo or to view guidelines to
help when hitching a 5th wheel or gooseneck
trailer. Zoom functionality also available.
To check the available camera views when in
Drive above 8 mph, touch the Camera icon on
the infotainment s creen and select the desired view. Touch X to exit the view.
ADDITIONAL TRAILER CAMERA VIEWSF
Multiple views to aid in trailering are shown on the infotainment screen using the vehicl e cameras and up to two additional wired acces-
sory camerasF mounted on the rear or interior of the trailer.
Touch the Rear Side View button for a
biased split view of each side of the trailer
(more of the left or right side will be shown
based on trailer position) and to view trailer
length when a turn signal is activated.
Touch the Transparent Trailer View button for a view behind the trailer.
Compatible with most conventional box
trailers; requires accessory cameraF.
Jack-Knife AlertF – The Jack-Knife Alert displays
a warning symbol when the truck/trailer angle is in a possible jack-knife position and
there is a potential imminent collision situation. The Safety Alert Seat
F may pulse or
beeps may sound.
Note: Accessory camera system compatible with most trailer and hitch types.
See Driving and Operating in your Owner’s Manual.
Surround Vision Rear Camera View screen
Bed View screen
Transparent Trailer View screen

17F Optional equipment
POWER MIRRORSF/TRAILERING MIRRORSF
POWER MIRROR ADJUSTMENT
Press the Mirror Selector button to select the driver or passenger side mirror; use the four-way control pad to adjust the mirror.
POWER FOLDING MIRROR
Press the Folding Mirror button to
fold or unfold the mirrors.
TRAILERING MIRRORS
The mirrors can be extended for better visibility when towing a trailer. The lower
wide-field view mirror adjusts manually.
To extend the manual mirror, grasp the
mirror housing and pull back and rear -
ward in one motion. The housing extends
on a curved arc. Push in the housing to
return the mirror to its original position.
Note: Reset the power mirrors if they are adjusted manually by using the power controls to fold/
unfold the mirrors to their normal position.
See Keys, Doors and Windows in your Owner’s Manual.
UNIVERSAL REMOTE SYSTEMF
The Universal Remote System on the overhead console enables your vehicle to control
3 different devices, ranging from garage doors and gates to home lighting. Go to
homelink.com for detailed videos and instructions on how to program the Universal
Remote System. For additional assistance, call 1-800-355-3515.
See Instruments and Controls in your Owner’s Manual.
HILL DESCENT CONTROLF
Hill Descent Control sets and maintains vehicle speed from 1–14 mph while descending
a steep incline in a forward or reverse gear.
1. Press the Hill Descent Control button on the center of the instrument panel.
Vehicle speed must be below 31 mph to enable the system. The
symbol will illuminate on the instrument cluster.
2. Increase or decrease speed by applying the accelerator or brake pedal or use the Cruise Control +/– buttons on the steering wheel. The adjusted speed becomes the
new set speed. The symbol flashes when the system is actively applying the
brakes to maintain vehicle speed.
See Driving and Operating in your Owner’s Manual.

18F Optional equipment
TRAILERINGF
PROGRADE TRAILERING SYSTEMF
The in-vehicle trailering app on the info-
tainment screen allows customized trailer
profiles with a variety of helpful towing
assistance features, including a hitching
and setup checklist, trailer tire pressure and
temperature monitoring
F, trailer light test-
ing, Jack-Knife Alert, trailer length indicator,
trailer theft detection and more. Trailering
App information also is available with the
myGMC mobile app.
Note: The Trailering App will monitor trailer presence, even while the vehicle is off, by periodically
checking the trailer lighting circuits. On trailers equipped with LED lights, these periodic checks may
cause the trailer lights to flash. This flashing will become more frequent if Theft Alert is enabled.
HITCH AREA LIGHTING
Press the Cargo Lamp button on the left side of the instrument panel to turn
the cargo bed lamp or conventional hitch lamp on/off.
TRAILERING INFORMATION LABEL
The Trailering information label, located by the driver’s door latch, provides vehicle-
specific weight information to help when loading the vehicle.
INTEGRATED TRAILER BRAKE CONTROL (ITBC)F
The ITBC system can be used to adjust the
power output, or Trailer Gain, to the trailer
brakes. The control panel is on the center
of the instrument panel. ITBC information
is displayed on the ITBC page on the Driver
Information Center.
Squeeze the control together (right s ide does not move) to manually apply the
trailer brakes.
Adjust the Trailer Gain by pressing the +/– adjustment buttons. See Driving and Operating in your Owner’s Manual.
TRUCK TIRE PRESSURE MONITORING SYSTEM
The Low Tire Pressure warning light on the instrument cluster illuminates when one
or more of the vehicle’s tires is significantly underinflated. Fill the tires to the proper tire
pressures listed on the Tire and Loading Information label, located below the driver’s
door latch. Current tire pressures can be viewed on the Driver Information Center.
With the ignition On or in Accessory mode, the Tire Fill Alert will provide visual and
audible alerts to help with inflating a tire to the recommended tire pressure (does not apply to spare tire). When the recommended pressure is reached, the horn sounds and
the turn signals change from flashing to solid.
Note: Refer to your Owner’s Manual for accessory trailer tire pressure monitoring system
information.
See Vehicle Care in your Owner’s Manual.

19
The tailgate has 6 functional positions to improve loading, unloading and access to the cargo box.
1. Primary Gate
Open the primary gate for ac cess to the cargo box.
2. Primary Gate Load Stop
With the primary gate open, the load stop helps keep longer items secure in the cargo box.
3. Easy Access
The inner ga te folds down for easier reach into the cargo box to access items near the cab.
4. Full-width Step
With the primary gate open, the inner gate folds into a sturdy step (up to 375 lbs.) with a conve-
nient handle for easy cargo box entry and exit.
5. Inner Gate Load Stop
With the primary gate closed, fold the inner gate for two-tier storage and open the load stop to
help keep longer items secure.
6. Inner Gate Work Surface
With the primary gate closed, fold the inner gate for two-tier storage or for use as a standing-
height work surface.
Note: Do not lower the inner gate with the primary gate
open if a hitch ball or trailer is attached.
OPEN THE INNER GATE
Press the upper button (A) on the tailgate.
OPEN THE PRIMARY GATE
Press the lower button (B) on the tailgate.
Press the Power Tailgate button twice on the
Remote Keyless Entry transmitter.
Press the Power Tailgate button on the center of the instrument panel.
OPEN THE PRIMARY
GATE AND INNER GATE
Press the lower button and then upper button
(B then A) on the tail -
gate consecutively.
OPEN THE LOAD STOP
OR STEP
Press the release bar (C).
GMC MULTIPRO TAILGATE OPERATIONF
F Optional equipmentSee Keys, Doors and Windows in your Owner’s Manual.
A
B
C
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3
4
5
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