2018 GMC SIERRA DENALI towing

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
In Brief 71. Instrument Panel Illumination
Control 0 182 .
2. Integrated Trailer Brake Control
(ITBC) System (If Equipped).
See Towing Equipment 0 325 .
3. Exterior Lamp Controls 0 176 .
Fog Lamps 0 181 (If
Equipped).
4. Air Vents 0 231 .
5. Turn Signal Lever. See Turn
and Lane-Change Signals
0 181 .
Windshield Wiper/Washer
0 130 .
6. Favorite Switches (Out of
View). See Steering Wheel
Controls 0 129 .
Volume Switches (Out of View).
See Steering Wheel Controls
0 129 .
7. Instrument Cluster 0 138 .
8. Hazard Warning Flashers
0 180 .
9. Shift Lever. See Automatic
Transmission 0 265 . Tow/Haul Selector Button (If
Equipped). See Tow/Haul
Mode 0 271 .
Range Selection Mode (If
Equipped). See Manual Mode
0 268 .
10. Light Sensor. See Automatic
Headlamp System 0 179 .
11. Infotainment 0 186 .
12. Passenger Airbag On-Off
Switch (If Equipped) (Out of
View). See Airbag On-Off
Switch 0 84 .
13. Heated and Ventilated Front
Seats 0 65 (If Equipped).
14. Power Outlet 110/120V
Alternating Current (If
Equipped). See Power Outlets
0 133 .
15. Power Outlets 0 133 (If
Equipped).
16. USB Port 0 197 (If Equipped).
17.
g Traction Control/Electronic
Stability Control 0 282 .0 Pedal Adjust Switch (If
Equipped). See Adjustable
Throttle and Brake Pedal
0 256 .
{ Cargo Lamp 0 183 .
X Parking Assist Button (If
Equipped). See Assistance
Systems for Parking or Backing
0 289 .
A Lane Keep Assist (LKA)
(1500 Series) 0 297 (If
Equipped).
5 Hill Descent Control Switch
(If Equipped). See Hill Descent
Control (HDC) 0 284 .
q Exhaust Brake Switch (If
Equipped). See “ Exhaust
Brake ” in the Duramax diesel
supplement.
g Power Take Off (PTO)
Switch (If Equipped). See the
Duramax diesel supplement.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
24 In Brief Automatic Transfer Case
This transfer case knob is to the left
of the steering column.
The different drive options that may
be available are described following.
2
m (Two-Wheel Drive High) : This
setting is used for driving in most
street and highway situations.
AUTO (Automatic Four-Wheel
Drive) : This setting is ideal for use
when road surface traction
conditions are variable. Do not use AUTO mode to park on
a steep grade with poor traction
such as ice, snow, mud or gravel. In
AUTO mode only the rear wheels
will hold the vehicle from sliding
when parked. If parking on a steep
grade, use 4
m to keep all four
wheels engaged.
4
m (Four-Wheel Drive High) : Use
this setting when extra traction is
needed, such as on snowy or icy
roads or in most off-road situations.
N (Neutral) : Shift to this setting
only when towing the vehicle.
See Recreational Vehicle Towing
0 430 or Trailer Towing 0 307 .
4
n (Four-Wheel Drive Low) : This
setting sends maximum power to all
four wheels. Choose 4
n when
driving in deep sand, mud, or snow,
and while climbing or descending
steep hills.
See Four-Wheel Drive 0 272 .Vehicle Features Infotainment System The base radio and base radio with
touchscreen information is included
in this manual. See the infotainment
manual for information on the
uplevel radios, audio players,
phone, navigation system, Rear
Seat Entertainment (RSE), and
voice or speech recognition,
if equipped.
Radio(s) Base Radio
O : Press to turn the system on.
Press and hold to turn it off. When
on, press to mute; press again to
unmute. Turn to increase or
decrease the volume.
RADIO : Press to choose between
FM, AM, and SiriusXM, if equipped.
MEDIA : Press to change the audio
source between CD, USB, AUX,
and Bluetooth Audio, if equipped.
{ : Press to go to the Home Page.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
48 Keys, Doors, and Windows Using hood-mounted air deflectors
and add-on convex mirror
attachments could decrease mirror
performance.
Trailer-Tow Mirrors
If equipped, adjust trailer-tow
mirrors for a clear view of the area
behind you. Manually pull out the
mirror head to extend it for better
visibility when towing a trailer.
The lower portion of the mirror is
convex. A convex mirror's surface is
curved to see more from the driver seat. The convex mirror can be
adjusted manually to the driver
preferred position for better vision.
The mirror may have a turn signal
arrow that flashes in the direction of
the turn or lane change.
Power Mirrors Using hood-mounted air deflectors
and add-on convex mirror
attachments could decrease mirror
performance.
Base Power Mirrors
The power mirror controls are on the
driver door. 1. Press (1) or (2) to select the
driver or passenger side mirror.
2. Press one of the four arrows on
the control pad to move the
mirror in the desired direction.
3. Adjust each outside mirror so
that a little of the vehicle and
the area behind it can be seen.
4. Move the selector switch to the
center position when not
adjusting either outside mirror.
Crew/Double Cab Premium
Shown, Other Models Similar
1. Press (1) or (2) to select the
driver or passenger side mirror.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
90 Seats and Restraints A thick layer of additional material,
such as a blanket or cushion,
or aftermarket equipment such as
seat covers, seat heaters, and seat
massagers can affect how well the
passenger sensing system
operates. We recommend that you
not use seat covers or other
aftermarket equipment except when
approved by GM for your specific
vehicle. See Adding Equipment to
the Airbag-Equipped Vehicle 0 90
for more information about
modifications that can affect how
the system operates.
The on indicator may be lit if an
object, such as a briefcase,
handbag, grocery bag, laptop,
or other electronic device, is put on
an unoccupied seat. If this is not
desired, remove the object from
the seat.
{ Warning
Stowing articles under the
passenger seat or between the
passenger seat cushion and
(Continued) Warning (Continued) seatback may interfere with the
proper operation of the passenger
sensing system.
Servicing the
Airbag-Equipped Vehicle Airbags affect how the vehicle
should be serviced. There are parts
of the airbag system in several
places around the vehicle. Your
dealer and the service manual have
information about servicing the
vehicle and the airbag system. To
purchase a service manual, see
Service Publications Ordering
Information 0 474 .
{ Warning
For up to 10 seconds after the
vehicle is turned off and the
battery is disconnected, an airbag
can still inflate during improper
service. You can be injured if you
(Continued) Warning (Continued) are close to an airbag when it
inflates. Avoid yellow connectors.
They are probably part of the
airbag system. Be sure to follow
proper service procedures, and
make sure the person performing
work for you is qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle Adding accessories that change the
vehicle's frame, bumper system,
height, front end, or side sheet
metal, may keep the airbag system
from working properly.
The operation of the airbag system
can also be affected by changing
any parts of the front seats, seat
belts, airbag sensing and diagnostic
module, steering wheel, instrument
panel, inner door seals including the
speakers, any of the airbag
modules, ceiling or pillar garnish

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Instruments and Controls 151If towing a trailer, reduce the
amount of cargo being hauled as
soon as possible.
If the light continues to flash, find a
safe place to park. Turn the vehicle
off and wait at least 10 seconds
before restarting the engine. If the
light is still flashing, follow the
previous guidelines and see your
dealer for service as soon as
possible.
If the light is on steady : A
malfunction has been detected.
Diagnosis and service may be
required.
Check the following:
.
A loose or missing fuel cap may
cause the light to come on. See
Filling the Tank 0 301 . A few
driving trips with the cap
properly installed may turn the
light off.
.
Poor fuel quality can cause
inefficient engine operation and
poor driveability, which may go
away once the engine is warmed
up. If this occurs, change the
fuel brand. It may require at least one full tank of the proper
fuel to turn the light off. See Fuel
0 299 .
If the light remains on, see your
dealer.
Emissions Inspection and
Maintenance Programs If the vehicle requires an Emissions
Inspection/Maintenance test, the
test equipment will likely connect to
the vehicle's Data Link
Connector (DLC).
The DLC is under the instrument
panel to the left of the steering
wheel. Connecting devices that are
not used to perform an Emissions
Inspection/Maintenance test or to
service the vehicle may affect
vehicle operation. See Add-On
Electrical Equipment 0 336 . See
your dealer if assistance is needed. The vehicle may not pass
inspection if:
.
The light is on when the engine
is running.
.
The light does not come on
when the ignition is on while the
engine is off.
.
Critical emission control systems
have not been completely
diagnosed. If this happens, the
vehicle would not be ready for
inspection and might require
several days of routine driving
before the system is ready for
inspection. This can happen if
the 12-volt battery has recently
been replaced or run down, or if
the vehicle has been recently
serviced.
See your dealer if the vehicle will
not pass or cannot be made ready
for the test.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
152 Instruments and Controls
Brake System Warning
Light The vehicle brake system consists
of two hydraulic circuits. If one
circuit is not working, the remaining
circuit can still work to stop the
vehicle. For normal braking
performance, both circuits need to
be working.
If the warning light comes on, there
is a brake problem. Have the brake
system inspected right away.
Metric English
This light should come on briefly
when the engine is started. If it does
not come on then, have it fixed so it
will be ready to warn you if there is
a problem.
When the ignition is on, the brake
system warning light also comes on
when the parking brake is set. The light stays on if the parking brake
does not fully release. If it stays on
after the parking brake is fully
released, it means the vehicle has a
brake problem.
If the light comes on while driving,
pull off the road and stop carefully.
The pedal might be harder to push,
or the pedal can go closer to the
floor. It may take longer to stop.
If the light is still on, have the
vehicle towed for service. See
Towing the Vehicle 0 430 .
{ WarningThe brake system might not be
working properly if the brake
system warning light is on.
Driving with the brake system
warning light on can lead to a
crash. If the light is still on after
the vehicle has been pulled off
the road and carefully stopped,
have the vehicle towed for
service. Antilock Brake System
(ABS) Warning Light
This light comes on briefly when the
engine is started.
If the light does not come on, have it
fixed so it will be ready to warn if
there is a problem.
If the light comes on while driving,
stop as soon as it is safely possible
and turn off the vehicle. Then start
the engine again to reset the
system. If the ABS light stays on,
or comes on again while driving, the
vehicle needs service. A chime may
also sound when the light comes on
steady.
If the ABS light is the only light on,
the vehicle has regular brakes, but
the antilock brakes are not
functioning.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 235Filling a Portable Fuel
Container . . . . . . . . . . . . . . . . . . . 303
Trailer Towing General Towing
Information . . . . . . . . . . . . . . . . . . 303
Driving Characteristics and
Towing Tips . . . . . . . . . . . . . . . . . 303
Trailer Towing . . . . . . . . . . . . . . . . 307
Towing Equipment . . . . . . . . . . . . 325
Trailer Sway Control (TSC) . . . 334
Conversions and Add-Ons Add-On Electrical
Equipment . . . . . . . . . . . . . . . . . . 336
Adding a Snow Plow or Similar
Equipment . . . . . . . . . . . . . . . . . . 337
Pickup Conversion to
Chassis Cab . . . . . . . . . . . . . . . . 340 Driving Information Distracted Driving Distraction comes in many forms
and can take your focus from the
task of driving. Exercise good
judgment and do not let other
activities divert your attention away
from the road. Many local
governments have enacted laws
regarding driver distraction. Become
familiar with the local laws in
your area.
To avoid distracted driving, keep
your eyes on the road, keep your
hands on the steering wheel, and
focus your attention on driving.
.
Do not use a phone in
demanding driving situations.
Use a hands-free method to
place or receive necessary
phone calls.
.
Watch the road. Do not read,
take notes, or look up
information on phones or other
electronic devices. .
Designate a front seat
passenger to handle potential
distractions.
.
Become familiar with vehicle
features before driving, such as
programming favorite radio
stations and adjusting climate
control and seat settings.
Program all trip information into
any navigation device prior to
driving.
.
Wait until the vehicle is parked
to retrieve items that have fallen
to the floor.
.
Stop or park the vehicle to tend
to children.
.
Keep pets in an appropriate
carrier or restraint.
.
Avoid stressful conversations
while driving, whether with a
passenger or on a cell phone.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 247
If the Vehicle Is Stuck Slowly and cautiously spin the
wheels to free the vehicle when
stuck in sand, mud, ice, or snow.
See “ Rocking the Vehicle to Get It
Out ” later in this section.
The Traction Control System (TCS)
can often help to free a stuck
vehicle. See Traction Control/
Electronic Stability Control 0 282 .
If TCS cannot free the vehicle, see
“ Rocking the Vehicle to Get it Out ”
following.
{ WarningIf the vehicle's tires spin at high
speed, they can explode, and you
or others could be injured. The
vehicle can overheat, causing an
engine compartment fire or other
damage. Spin the wheels as little
as possible and avoid going
above 56 km/h (35 mph).
For information about using tire
chains on the vehicle, see Tire
Chains 0 413 . Rocking the Vehicle to Get
It Out Turn the steering wheel left and
right to clear the area around the
front wheels. For four-wheel-drive
vehicles, shift into Four-Wheel Drive
High. Turn the TCS off. Shift back
and forth between R (Reverse) and
a forward gear, spinning the wheels
as little as possible. To prevent
transmission wear, wait until the
wheels stop spinning before shifting
gears. Slowly spinning the wheels in
the forward and reverse directions
causes a rocking motion that could
free the vehicle. If that does not get
the vehicle out after a few tries, it
might need to be towed out. See
Towing the Vehicle 0 430 . Recovery
hooks can be used, if the vehicle
has them. Recovery Hooks
{ WarningNever pull on recovery hooks
from the side. The hooks could
break and you and others could
be injured. When using recovery
hooks, always pull the vehicle
from the front.