
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
276 Driving and Operating
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 Vehicle 0 398 . To tow
the vehicle behind another vehicle
such as a motor home, see
Recreational Vehicle Towing 0 399 .
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-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 279The vehicle can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts too
often under heavy loads and/or hilly
conditions.
When towing at higher altitudes,
engine coolant will boil at a lower
temperature than at lower altitudes.
If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle could show signs similar to
engine overheating. To avoid this,
let the engine run, preferably on
level ground, with the transmission
in P (Park) for a few minutes before
turning the engine off. If the
overheat warning comes on, see
Engine Overheating 0 331 .
Viewing Systems If equipped, the viewing systems on
the vehicle can improve visibility
while hitching, backing, and driving
with a trailer. See Driver Assistance
Systems 0 253 . Parking on Hills
{ WarningTo prevent serious injury or death,
always park your vehicle and
trailer on a level surface when
possible.
When parking your vehicle and your
trailer on a hill:
1. Press the brake pedal, but do
not shift into P (Park) yet. Turn
the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks
under the trailer wheels.
3. When the wheel chocks are in
place, gradually release the
brake pedal to allow the chocks
to absorb the load of the trailer.
4. Reapply the brake pedal. Then
apply the parking brake and
shift into P (Park).
5. Release the brake pedal. Leaving After Parking on a Hill 1. Apply and hold the brake
pedal.
.
Start the engine.
.
Shift into a gear.
.
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is
clear of the chocks.
4. Stop and have someone pick
up and store the chocks.
Launching and Retrieving
a Boat Backing the Trailer into the Water
{ Warning
.
Have all passengers get out
of the vehicle before
backing onto the sloped part
of the ramp. Lower the
driver and passenger side
windows before backing
onto the ramp. This will
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
280 Driving and Operating Warning (Continued) provide a means of escape
in the unlikely event the
vehicle slides into the water.
.
If the boat launch surface is
slippery, have the driver
remain in the vehicle with
the brake pedal applied
while the boat is being
launched. The boat launch
can be especially slippery at
low tide when part of the
ramp was previously
submerged at high tide. Do
not back onto the ramp to
launch the boat if you are
not sure the vehicle can
maintain traction.
.
Do not move the vehicle if
someone is in the path of
the trailer. Some parts of the
trailer might be underwater
and not visible to people
who are assisting in
launching the boat. Disconnect the wiring to the trailer
before backing the trailer into the
water to prevent damage to the
electrical circuits on the trailer.
Reconnect the wiring to the trailer
after removing the trailer from the
water. If the trailer has electric
brakes that can function when the
trailer is submerged, it might help to
leave the electrical trailer connector
attached to maintain trailer brake
functionality while on the boat ramp.
To back the trailer into the water:
1. If equipped, place the vehicle
in four-wheel-drive high.
2. Slowly back down the boat
ramp until the boat is floating,
but no further than necessary.
3. Press and hold the brake
pedal, but do not shift into
P (Park) yet.
4. Have someone place chocks
under the front wheels of the
vehicle.
5. Gradually release the brake
pedal to allow the chocks to
absorb the load of the trailer. 6. Reapply the brake pedal. Then
apply the parking brake and
shift into P (Park).
7. Release the brake pedal.
Pulling the Trailer from the Water
To pull the trailer of the water:
1. Press and hold the brake
pedals.
2. Start the engine and shift
into gear.
3. Release the parking brake.
4. Let up on the brake pedal.
5. Drive slowly until the tires are
clear of the chocks.
6. Stop and have someone pick
up and store the chocks.
7. Slowly pull the trailer from the
water.
8. Once the vehicle and trailer
have been driven from the
sloped part of the boat ramp,
the vehicle can be shifted from
four-wheel-drive high. Shift into

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 289Electric Brake Control Wiring
Provisions If the vehicle is not equipped with
an integrated trailer brake controller,
and the trailer has electric brakes, a
trailer brake controller needs to be
installed on the vehicle. The brake
controller should be installed by
your dealer or a qualified service
center.
If equipped, there is a trailer brake
jumper harness provided with the
vehicle. The connector on the trailer
brake jumper harness is attached to
a mating connector to the left of the
steering wheel behind the knee
bolster. The four blunt cut wires on
the jumper harness need to be
connected to an aftermarket electric
trailer brake controller. The harness
contains the following circuits:
Electric Trailer
Brakes Blue
Battery Feed Red/Violet or
Red/Black
Brake Apply
Signal White/Blue Ground Black
The fuse for the electric trailer brake
circuit is in the engine compartment
fuse block, but the wires may not be
connected. They should be
connected by your dealer or a
qualified service center.
Refer to the aftermarket electric
trailer brake controller owner's
manual to determine wire color
coding of the electric trailer brake
controller. The wire colors on the
brake controller may be different
from the vehicle.
Trailer Lamps Always check all trailer lamps are
working at the beginning of each
trip, and periodically on longer trips.
If equipped, the trailering app will
monitor the brake lamps, turn signal
lamps, running lamps and reverse
lamps on the trailer. DIC messages
may be displayed if lighting circuit
issues are detected on the trailer. The trailer bulbs can be observed
by starting the trailer light test
sequence. See Trailering App
0 296 .
Turn Signals When Towing a
Trailer When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing
lanes, or stopping. When towing a
trailer, the arrows on the instrument
cluster will illuminate even if the
trailer is not properly connected or
the bulbs are burned out.
Tow/Haul Mode For instructions on how to enter
Tow/Haul Mode, see Driver Mode
Control 0 246 .
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. See Tow/Haul Mode 0 234 .
Tow/Haul Mode is designed to be
most effective when the vehicle and
trailer combined weight is at least
75% of the vehicle's Gross

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
296 Driving and Operating
Trailering App Trailer Light App If equipped, the Trailer Lights App is
on the Home Page of the
infotainment display.
Touch Start to cycle the trailer lights
on and off to determine if they are
working. The test follows this
sequence:
1. The running lights turn on first
and remain on throughout the
sequence.
2. The brake lights turn on for
about two seconds.
3. The left turn signal light flashes
three times.
4. The right turn signal light
flashes three times.
5. The reverse lights turn on for
about two seconds.
6. Steps 2 – 5 repeat for
approximately one minute and
45 seconds, or until the test
deactivates. Touch Stop to stop the test. The test
will automatically end after
one minute and 45 seconds.
The sequence also deactivates
when any of the following occur:
.
The ignition is turned off.
.
The transmission is shifted out
of P (Park).
.
The brake pedal pressed.
.
The turn signal is activated.
.
The hazard warning lights
activated.
Trailering App If equipped, the Trailering App is on
the Home Page of the infotainment
display.
This feature allows profiles for
connected trailers to be created to
view status, and to store and track
trailer usage information.
The Trailering App Preview will
appear when the Trailering App is
opened for the first time from the Home Page. Touch GET STARTED
in the Trailering App to go into
the app.
When a trailer is electrically
connected, there will be an option to
create a profile, use a guest profile,
or cancel. After Cancel is selected a
third time, Don ’ t Remind Me will
display and touching that will turn off
the trailer detection pop-up. To turn
the Trailer Detection Alert on, select
ON in the Settings tab.
When a trailer is electrically
connected and after a Trailer Profile
has been created, the trailer
detection pop-up will appear with a
list of all of the custom Trailer
Profiles made on the vehicle. To
load an existing Trailer Profile,
select one of the Trailer Profiles
listed, or load the Guest Trailer
Profile by selecting GUEST
TRAILER. Touching Cancel,
Accessory/No trailer, or shifting the
vehicle from P (Park), will select
Accessory/No trailer as the active
Trailer Profile and will dismiss the
pop- up.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 297Create a Trailer Profile
1. Touch Create Profile on the
pop-up or touch + New Trailer
in the Trailering App.
2. Create a name for the trailer.
3. Select the hitch type.
A checklist profile will be
created based on the type
selected.
4. Select the trailer type.
A pop-up will indicate the setup is
complete. Touch DONE to complete
the process or touch ADVANCED
SETUP to set up the Tow/Haul
Mode reminder, Trailer Tire
Pressure Monitoring System,
if equipped, or maintenance
reminders.
Advanced Setup
Tow/Haul Mode Reminder
To turn the Tow/Haul Mode
Reminder setting on, touch Yes. To
turn it off, touch No. Trailer Tire Pressure Setup
If the Trailer Tire Pressure
Monitoring System (TTPMS) is
detected, touch Yes to set up the
sensors or touch No to skip this
step and go to the Maintenance
Reminders step.
If the vehicle is not equipped with
TTPMS, the app will advance
directly to the Maintenance
Reminders screen. Follow the
on-screen instructions.
A trailer must be electrically
connected to the vehicle before
starting the sensor-to-vehicle learn
process.
After selecting Start from the Learn
Sensors screen, use the Tool
Method or the Manual Method
(described below) to learn each tire
sensor, during which the current tire
number will be highlighted.
Each sensor has a minimum of
two minutes to learn, shown by a
timer. After a sensor is learned, a
checkmark appears next to the tire,
the vehicle horn will sound, the vehicle ’ s brake lamps will flash, and
all working trailer lamps will flash.
It then moves to the next sensor.
To cancel the process touch Stop.
The recommended tire pressure
must be entered for the trailer tires.
This allows the vehicle to alert when
the tire pressure is high or low.
TTPMS must learn the location of
the installed tire sensors to show
correct air pressure and
temperature for each tire. To set up,
use one of the following options or
see a tire or trailer dealer for
service. The learning process must
be repeated when the trailer tires
are rotated or replaced. See “ Editing
a Trailer Profile ” later in this section
for tire pressure sensor relearn
information.
Tool Method: A TTPMS activation
tool can be purchased separately to
learn the sensor locations.
Manual Method: Without the tool,
the air pressure can be increased or
decreased in each tire for
10 seconds. Do not exceed the
maximum inflation pressure found

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
298 Driving and Operating on the tire sidewalls. Make sure to
re-adjust tire pressure to the
recommended level when the
process is complete.
Sensor Learning Steps
To complete the sensor-to-vehicle
learn process:
1. Touch Start on the Learn
Sensors screen. The horn
chirps twice and the Learning
Active screen appears on the
infotainment display.
2. Start with the driver side front
trailer tire.
3. Activate the tool near the valve
stem or adjust the air pressure
of this tire until the horn chirps
and all working vehicle and
trailer lights flash.
The process stops without
saving the sensor locations if
this step takes more than
two minutes.
4. Move to the next tire and
repeat Step 3 for each sensor.
The horn chirps twice when all
sensors are completed. 5. Return to the vehicle to
complete the setup.
Maintenance Reminders Select Yes to set up the
maintenance reminders for the
Trailer Profile. Follow the on-screen
prompts. The maximum number of
reminders is 10. Select No to skip
this step.
Status View The Status view shows:
.
Truck
.
Connection
.
Trailer
.
Maintenance Truck
1. Truck Status Page
2. Transmission Temperature
3. Average Fuel Economy with
Trailer Profile
Average Fuel Economy
Touch to view the average fuel
economy of the vehicle while the
Trailer Profile is active.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Vehicle Care 311
Vehicle Care General Information General Information . . . . . . . . . . 312
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 313
California Perchlorate
Materials Requirements . . . . . 313
Accessories and
Modifications . . . . . . . . . . . . . . . . 313
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 314
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 314
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . . 316
Engine Oil . . . . . . . . . . . . . . . . . . . . 321
Engine Oil Life System . . . . . . . 323
Automatic Transmission
Fluid . . . . . . . . . . . . . . . . . . . . . . . . 325
Engine Air Filter Life
System . . . . . . . . . . . . . . . . . . . . . . 325
Engine Air Cleaner/Filter . . . . . . 326
Cooling System . . . . . . . . . . . . . . 327
Engine Overheating . . . . . . . . . . 331
Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . 333
Engine Fan . . . . . . . . . . . . . . . . . . . 333 Washer Fluid . . . . . . . . . . . . . . . . . 334
Brakes . . . . . . . . . . . . . . . . . . . . . . . 335
Brake Pad Life System . . . . . . . 335
Brake Fluid . . . . . . . . . . . . . . . . . . . 336
Battery - North America . . . . . . 337
Four-Wheel Drive . . . . . . . . . . . . . 340
Front Axle . . . . . . . . . . . . . . . . . . . . 340
Rear Axle . . . . . . . . . . . . . . . . . . . . 341
Noise Control System . . . . . . . . 342
Starter Switch Check . . . . . . . . . 343
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 343
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 343
Wiper Blade Replacement . . . . 344
Windshield Replacement . . . . . 345
Gas Strut(s) . . . . . . . . . . . . . . . . . . 345
Headlamp Aiming Headlamp Aiming . . . . . . . . . . . . 346
Bulb Replacement Bulb Replacement . . . . . . . . . . . . 346
Halogen Bulbs . . . . . . . . . . . . . . . . 346
LED Lighting . . . . . . . . . . . . . . . . . 347
Headlamps, Front Turn Signal,
Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 347
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 347 Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 348
License Plate Lamp . . . . . . . . . . 349
Electrical System Electrical System Overload . . . 349
Fuses and Circuit Breakers . . . 350
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 350
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . . . 354
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 356
Wheels and Tires Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 358
All-Season Tires . . . . . . . . . . . . . . 359
Winter Tires . . . . . . . . . . . . . . . . . . 359
Low-Profile Tires . . . . . . . . . . . . . 360
All-Terrain Tires . . . . . . . . . . . . . . . 360
Tire Sidewall Labeling . . . . . . . . 360
Tire Designations . . . . . . . . . . . . . 363
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 364
Tire Pressure . . . . . . . . . . . . . . . . . 367
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . 368
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 369