
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
42 Keys, Doors, and Windows
Manual Extend :If equipped, grasp
the mirror housing firmly and pull
back in one motion, arching slightly
toward the rear of the vehicle.
To return the mirror to its original
position, reverse the motion.
Power Extend : If equipped, press
the power extend button to fully
extend the mirror. Press again to
retract.
Resetting the Power Extend
Mirrors
Reset the power extend mirrors if:
. The mirrors are accidentally
obstructed while extending/
retracting.
. The mirrors are accidentally
manually extended/retracted.
. The mirrors vibrate at normal
driving speeds. If a popping noise from the mirror is
heard, this sound is normal as the
manual detents are aligning after a
manual extend/retract operation has
occurred.
Auxiliary Cargo Mirror Lamps
If equipped, cargo mirror lamps face
rearward to provide more light on
the sides of the vehicle, if needed.
See
Exterior Cargo Lamps 0171.
Advanced Trailering Vision
System Side Cameras
If equipped, the Advanced Trailering
Vision System side cameras are on
the bottom of the outside mirrors.
See “Surround Vision (360
Degrees)” underAssistance
Systems for Parking or Backing
0 257.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
186 Driving and Operating
Lane Change Alert (LCA) . . . . . 274
Lane Departure Warning(LDW) (2500/3500
Series) . . . . . . . . . . . . . . . . . . . . . . 276
Lane Keep Assist (LKA) (1500
Series) . . . . . . . . . . . . . . . . . . . . . . 278
Fuel
Top Tier Fuel . . . . . . . . . . . . . . . . . 280
Recommended Fuel (Except6.2L V8 Engine) . . . . . . . . . . . . . 280
Recommended Fuel (6.2L V8 Engine) . . . . . . . . . . . . . . . . . . 281
Prohibited Fuels . . . . . . . . . . . . . . 281
Fuels in Foreign Countries . . . 281
Fuel Additives . . . . . . . . . . . . . . . . 282
E85 or FlexFuel . . . . . . . . . . . . . . 282
Filling the Tank (Pickup Model) . . . . . . . . . . . . . . . . . . . . . . 283
Filling the Tank (Chassis Cab Model) . . . . . . . . . . . . . . . . . . . . . . 285
Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . . 286
Trailer Towing
General TowingInformation . . . . . . . . . . . . . . . . . . 287
Driving Characteristics and Towing Tips . . . . . . . . . . . . . . . . . 287
Trailer Towing . . . . . . . . . . . . . . . . 292
Towing Equipment . . . . . . . . . . . . 296 Trailer Sway Control (TSC) . . . 308
Trailering App . . . . . . . . . . . . . . . . 310
Conversions and Add-Ons
Add-On Electrical
Equipment . . . . . . . . . . . . . . . . . . 322
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . . . . . . . . 323
Pickup Conversion to Chassis Cab . . . . . . . . . . . . . . . . 326
Driving Information
Driving for Better Fuel
Economy
Driving habits can affect fuel
mileage. Here are some driving tips
to get the best fuel economy
possible:
. Set the climate controls to the
desired temperature after the
engine is started, or turn them
off when not required.
. Avoid fast starts and accelerate
smoothly.
. Brake gradually and avoid
abrupt stops.
. Avoid idling the engine for long
periods of time.
. When road and weather
conditions are appropriate, use
cruise control.
. Always follow posted speed
limits or drive more slowly when
conditions require.
. Keep vehicle tires properly
inflated.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
202 Driving and Operating
exceed the available cargo
and luggage load capacity
calculated in Step 4.
6.If your vehicle will be towing
a trailer, load from your
trailer will be transferred to
your vehicle. Consult this
manual to determine how
this reduces the available
cargo and luggage load
capacity of your vehicle.”
See Trailer Towing 0292 for
important information on towing
a trailer, towing safety rules, and
trailering tips.
Example 1
1. Vehicle Capacity Weight for
Example 1 = (453 kg)
(1,000 lb)
2. Subtract Occupant Weight @ 68 kg (150 lb) × 2 =
136 kg (300 lb)
3. Available Occupant and Cargo Weight = 317 kg
(700 lb)
Example 2
1. Vehicle Capacity Weight forExample 2 = 453 kg
(1,000 lb)
2. Subtract Occupant Weight @ 68 kg (150 lb) × 5 =
340 kg (750 lb)
3. Available Cargo Weight = 113 kg (250 lb)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
262 Driving and Operating
gooseneck trailer. To select,
touch Bed View on the
infotainment display when a
camera view is active. To
access this view when in a
forward gear above 12 km/h
(8 mph), touch CAMERA on
the infotainment display
and touch the Bed View
icon. The view will close
after 8 seconds and can be
closed early by touching X.
10. Transparent Trailer View
Provides a view that allows
the driver to virtually“see
through” the trailer. The
feature is available when a
compatible trailer is
connected and a profile is
configured and selected via
the Trailering App. See
Trailering App 0310. The
feature requires user
installation of an accessory
trailer camera on the rear
exterior surface of the
trailer per the accessory
trailer camera installation
instructions (see your dealer for accessory trailer
camera(s) and information).
To select, touch
Transparent Trailer View on
the infotainment display
when a camera view is
active. To access this view
when in a forward gear
above 12 km/h (8 mph),
touch CAMERA on the
infotainment display and
touch the Transparent
Trailer View icon. Touch X
to exit.
When the system is
calibrated and the trailer
position is known, one of
three views will be shown;
Transparent Trailer View,
Left Transparent Trailer
View or Right Transparent
Trailer View. The
Transparent Trailer View is
shown when the position of
the trailer is relatively
straight behind the vehicle.
The Left or Right
Transparent Trailer View is
shown when the position of
the trailer is too far to theleft or right. When the
system is not calibrated or
trailer position is not known
the Transparent Trailer
Picture-in-Picture View will
be shown.
11. Rear Trailer View/Rear Side
View with Available
Articulation Functionality/
Picture-in-Picture Side View
.Rear Trailer View
provides a view of the
area behind the trailer.
the feature is available
when a trailer is
connected. The feature
requires user installation
of an accessory trailer
camera on the rear
exterior surface of the
trailer per the accessory
trailer camera
installation instructions
(see your dealer for
accessory trailer
camera(s) and
information). To select,
touch Rear Trailer View/
Rear Side View with

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
264 Driving and Operating
display when a camera
view is active. Each
press of the button will
toggle through the Rear
Trailer View, Trailer Tow
mirror View and Combo
View. To access this
view when in a forward
gear above 12 km/h
(8 mph), touch
CAMERA on the
infotainment display and
touch the Rear Trailer
View/Rear Side View
with Available
Articulation
Functionality/
Picture-in-Picture Side
View icon. Touch X
to exit.
HD Surround Vision with Trailer
Camera Provisions
If equipped, this feature provides
additional views to aid in trailering/
towing. The system shows multiple
views in the infotainment display
using five cameras mounted around
the vehicle and up to two additional
accessory cameras that can be mounted on or in a trailer. The front
camera is in the grille under the
front emblem, the side cameras are
on the bottom of the outside mirrors,
the rear camera is in the tailgate
handle and the bed camera is
mounted on the rear of the cab.
Additionally, up to two accessory
cameras can be mounted to the rear
and/or interior of the trailer. See
your dealer for accessory trailer
cameras. To access, touch
CAMERA on the infotainment
display or shift to R (Reverse). To
return to the previous screen when
not in reverse, touch the Home or
Back buttons on the infotainment
display.
Available camera views:
.
Front/Rear Standard View
. Front/Rear Top-Down View
. Rear Bowl View
. Front/Rear Side View
. Hitch View
. Bed View
. Rear trailer View .
Rear Side view with a available
articulation functionality
. Picture-in-Picture Side View
. Interior Trailer View
. Transparent trailer View
. Surround View
. Guidance Lines
. Hitch Guidance
Surround Vision (360 Degrees)
If equipped, the Surround Vision
system can display various views
surrounding the vehicle in the
infotainment display using four
cameras mounted around the
vehicle. The front camera is in the
grille under the front emblem, the
side cameras are on the bottom of
the outside mirrors, and the rear
camera is in the tailgate handle.
The Surround Vision system can be
accessed by selecting CAMERA in
the infotainment display or when the
vehicle is shifted into R (Reverse).
To return to the previous screen
sooner, when not in R (Reverse),
press the Home or Back button on

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Driving and Operating 265
the infotainment system, shift into
P (Park), or, while in D (Drive),
reach a vehicle speed of
approximately 12 km/h (8 mph).
Available camera views:
.Front/Rear Standard View
. Front/Rear Top-Down View
. Rear Bowl View
. Front/Rear Side View
. Hitch View
. Surround View
. Guidance Lines
. Hitch Guidance
Surround Vision
If equipped, this feature provides,
additional views to aid in trailering/
towing. The Front Vision Camera
and Surround Vision cameras are
not supported. The system can
show various views in the
infotainment display using cameras
mounted in and around the vehicle
and trailer. The rear camera is in the
tailgate handle and the cargo bed
camera is mounted on the rear of the cab. Up to two accessory
cameras can be mounted to the rear
and/or interior of the trailer. See
your dealer for these accessory
cameras.
The system can be accessed by
selecting CAMERA in the
infotainment display or when the
vehicle is shifted into R (Reverse).
To return to the previous screen
sooner, when not in R (Reverse),
press the Home or Back button on
the infotainment system or shift into
P (Park).
Available camera views:
.
Rear Standard View
. Hitch View
. Bed View
. Rear Trailer View
. Interior Trailer View
. Guidance Lines
. Hitch Guidance Troubleshooting
The Transparent Trailer calibration
may take longer than expected or
not calibrate if:
.
The vehicle is driven too fast
during calibration. Speed should
be maintained below 50 km/h
(31 mph).
. The vehicle is not driven straight
during calibration. Steering
should be maintained as straight
as possible, excessive steering
during calibration may extend
calibration time.
. The calibration is attempted in
low light. Calibration should be
attempted when there is enough
light.
. The calibration is attempted
during adverse weather
conditions. Calibration during
conditions such as snow or
heavy rain should be avoided.
. The road surface is not ideal for
calibration. Calibration should be
attempted on an alternate road
surface.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Driving and Operating 287
Trailer Towing
General Towing
Information
Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle to tow a trailer. Read the
entire section before towing a trailer.
To tow a disabled vehicle, see
Towing the Vehicle0424. To tow
the vehicle behind another vehicle
such as a motor home, see
Recreational Vehicle Towing 0424.
Driving Characteristics
and Towing Tips
{Warning
You can lose control when towing
a trailer if the correct equipment is
not used or the vehicle is not
driven properly. For example,
if the trailer is too heavy or the
(Continued)
Warning (Continued)
trailer brakes are inadequate for
the load, the vehicle may not stop
as expected. You and others
could be seriously injured. The
vehicle may also be damaged,
and the repairs would not be
covered by the vehicle warranty.
Pull a trailer only if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer
with the vehicle.
Driving with a Trailer
Trailering is different than just
driving the vehicle by itself.
Trailering means changes in
handling, acceleration, braking,
durability, and fuel economy.
Successful, safe trailering takes
correct equipment, and it has to be
used properly.
The following information has many
time-tested, important trailering tips
and safety rules. Many of these are important for your safety and that of
your passengers. Read this section
carefully before pulling a trailer.
When towing a trailer:
.
Become familiar with and follow
all state and local laws that
apply to trailer towing. These
requirements vary from state to
state.
. State laws may require the use
of extended side view mirrors.
Even if not required, you should
install extended side view
mirrors if your visibility is limited
or restricted while towing.
. Do not tow a trailer during the
first 800 km (500 mi) of vehicle
use to prevent damage to the
engine, axle, or other parts.
. It is recommended to perform
the first oil change before heavy
towing.
. During the first 800 km (500 mi)
of trailer towing, do not drive
over 80 km/h (50 mph) and do
not make starts at full throttle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
292 Driving and Operating
the drive mode that is
appropriate for the road
conditions.
Caution
If the vehicle tires begin to spin
and the vehicle begins to slide
toward the water, remove your
foot from the accelerator pedal
and apply the brake pedal. Seek
help to have the vehicle towed up
the ramp.
Maintenance when Trailer
Towing
The vehicle needs service more
often when used to tow trailers. See
Maintenance Schedule0442. It is
especially important to check the
engine oil, axle lubricant, belts,
cooling system, and brake system
before and during each trip.
Check periodically to see that all
nuts and bolts on the trailer hitch
are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See Engine Overheating
0 351.
Trailer Towing
If equipped with a diesel engine,
see the Duramax diesel
supplement.
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer
for important information about
towing a trailer with the vehicle.
Trailering is different than just
driving the vehicle by itself.
Trailering means changes in
handling, acceleration, braking,
durability, and fuel economy. Successful, safe trailering takes
correct equipment, and it has to be
used properly.
The following information has many
time-tested, important trailering tips
and safety rules. Many of these are
important for your safety and that of
your passengers. Read this section
carefully before pulling a trailer.
Trailer Weight
{Warning
Never exceed the towing capacity
for your vehicle.
Safe trailering requires monitoring
the weight, speed, altitude, road
grades, outside temperature, and
how frequently the vehicle is used to
tow a trailer.
Trailer Weight Ratings
When towing a trailer, the combined
weight of the vehicle, vehicle
contents, trailer, and trailer contents