2020 GMC YUKON trailer

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
248 Driving and Operating
.Clean the headlamps.
For cleaning instructions, see
“Washing the Vehicle” under
Exterior Care 0367.
System operation may also be
limited under snow, heavy rain,
or road spray conditions.
Automatic Emergency
Braking (AEB)
If the vehicle has Forward Collision
Alert (FCA), it also has AEB, which
includes Intelligent Brake
Assist (IBA). When the system
detects a vehicle ahead in your path
that is traveling in the same
direction that you may be about to
crash into, it can provide a boost to
braking or automatically brake the
vehicle. This can help avoid or
lessen the severity of crashes when
driving in a forward gear. Depending
on the situation, the vehicle may
automatically brake moderately or
hard. This automatic emergency
braking can only occur if a vehicle is
detected. This is shown by the FCA vehicle ahead indicator being lit.
See
Forward Collision Alert (FCA)
System 0245.
The system works when driving in a
forward gear between 8 km/h
(5 mph) and 80 km/h (50 mph),
or on vehicles with Adaptive Cruise
Control (ACC), above 4 km/h
(2 mph). It can detect vehicles up to
approximately 60 m (197 ft).{Warning
AEB is an emergency crash
preparation feature and is not
designed to avoid crashes. Do
not rely on AEB to brake the
vehicle. AEB will not brake
outside of its operating speed
range and only responds to
detected vehicles.
AEB may not: . Detect a vehicle ahead on
winding or hilly roads.
(Continued)
Warning (Continued)
.Detect all vehicles,
especially vehicles with a
trailer, tractors, muddy
vehicles, etc.
. Detect a vehicle when
weather limits visibility, such
as in fog, rain, or snow.
. Detect a vehicle ahead if it
is partially blocked by
pedestrians or other objects.
Complete attention is always
required while driving, and you
should be ready to take action
and apply the brakes and/or steer
the vehicle to avoid crashes.
AEB may slow the vehicle to a
complete stop to try to avoid a
potential crash. The vehicle will only
hold at a stop briefly. A firm press of
the accelerator pedal will also
release AEB.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 249
{Warning
AEB may automatically brake the
vehicle suddenly in situations
where it is unexpected and
undesired. It could respond to a
turning vehicle ahead, guardrails,
signs, and other non-moving
objects. To override AEB, firmly
press the accelerator pedal, if it is
safe to do so.
Intelligent Brake Assist (IBA)
IBA may activate when the brake
pedal is applied quickly by providing
a boost to braking based on the
speed of approach and distance to
a vehicle ahead.
Minor brake pedal pulsations or
pedal movement during this time is
normal and the brake pedal should
continue to be applied as needed.
IBA will automatically disengage
only when the brake pedal is
released.
{Warning
IBA may increase vehicle braking
in situations when it may not be
necessary. You could block the
flow of traffic. If this occurs, take
your foot off the brake pedal and
then apply the brakes as needed.
AEB and IBA can be disabled
through vehicle personalization. See
“Collision/Detection Systems” under
Vehicle Personalization 0152.
{Warning
Using AEB or IBA while towing a
trailer could cause you to lose
control of the vehicle and crash.
Turn the system to Alert, or if the
vehicle has ACC to Off, when
towing a trailer.
A system unavailable message may
display if:
. The front of the vehicle or
windshield is not clean. .
Heavy rain or snow is interfering
with object detection.
. There is a problem with the
StabiliTrak/Electronic Stability
Control (ESC) system.
The AEB system does not need
service.
Side Blind Zone
Alert (SBZA)
If equipped, the SBZA system is a
lane-changing aid that assists
drivers with avoiding crashes that
occur with moving vehicles in the
side blind zone (or spot) areas.
When the vehicle is in a forward
gear, the left or right side mirror
display will light up if a moving
vehicle is detected in that blind
zone. If the turn signal is activated
and a vehicle is also detected on
the same side, the display will flash
as an extra warning not to change
lanes. Since this system is part of
the Lane Change Alert (LCA)
system, read the entire LCA section
before using this feature.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 251
blind zone or rapidly approaching
that zone. If the turn signal is
activated in the same direction as a
detected vehicle, this display will
flash as an extra warning not to
change lanes.
LCA can be disabled through
vehicle personalization. When you
disable LCA, Side Blind Zone Alert
is also disabled. See“Collision/
Detection Systems” underVehicle
Personalization 0152. If LCA is
disabled by the driver, the LCA
mirror displays will not light up.
When the System Does Not
Seem to Work Properly
The LCA system requires some
driving for the system to calibrate to
maximum performance. This
calibration may occur more quickly if
the vehicle is driving on a straight
highway road with traffic and
roadside objects (e.g., guardrails,
barriers).
LCA displays may not come on
when passing a vehicle quickly, for
a stopped vehicle, or when towing a
trailer. The LCA detection zones that extend back from the side of
the vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer. LCA may alert to objects
attached to the vehicle, such as a
trailer, bicycle, or object extending
out to either side of the vehicle.
Attached objects may also interfere
with the detection of vehicles. This
is normal system operation; the
vehicle does not need service.
LCA may not always alert the driver
to vehicles in the next lane over,
especially in wet conditions or when
driving on sharp curves. The system
does not need to be serviced. The
system may light up due to
guardrails, signs, trees, shrubs, and
other non-moving objects. This is
normal system operation; the
vehicle does not need service.
LCA may not operate when the LCA
sensors in the left or right corners of
the rear bumper are covered with
mud, dirt, snow, ice, or slush, or in
heavy rainstorms. For cleaning
instructions, see "Washing the
Vehicle" under
Exterior Care0367. If the DIC still displays the system
unavailable message after cleaning
both sides of the vehicle toward the
rear corners of the vehicle, see your
dealer.
If the LCA displays do not light up
when moving vehicles are in the
side blind zone or are rapidly
approaching this zone and the
system is clean, the system may
need service. Take the vehicle to
your dealer.
Radio Frequency Information
See
Radio Frequency Statement
0 405.
Lane Keep Assist (LKA)
If equipped, LKA may help avoid
crashes due to unintentional lane
departures. This system uses a
camera to detect lane markings
between 60 km/h (37 mph) and
180 km/h (112 mph). It may assist by
gently turning the steering wheel if
the vehicle approaches a detected
lane marking. It may also provide a
Lane Departure Warning (LDW)
alert if the vehicle crosses a

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
252 Driving and Operating
detected lane marking. LKA can be
overridden by turning the steering
wheel. This system is not intended
to keep the vehicle centered in the
lane. LKA will not assist and alert if
the turn signal is active in the
direction of lane departure, or if it
detects that you are accelerating,
braking or actively steering.
{Warning
The LKA system does not
continuously steer the vehicle.
It may not keep the vehicle in the
lane or give a Lane Departure
Warning (LDW) alert, even if a
lane marking is detected.
The LKA and LDW systems
may not:. Provide an alert or enough
steering assist to avoid a
lane departure or crash.
. Detect lane markings under
poor weather or visibility
conditions. This can occur if
the windshield or
(Continued)
Warning (Continued)
headlamps are blocked by
dirt, snow, or ice; if they are
not in proper condition; or if
the sun shines directly into
the camera.
. Detect road edges.
. Detect lanes on winding or
hilly roads.
If LKA only detects lane markings
on one side of the road, it will
only assist or provide an LDW
alert when approaching the lane
on the side where it has detected
a lane marking. Even with LKA
and LDW, you must steer the
vehicle. Always keep your
attention on the road and
maintain proper vehicle position
within the lane, or vehicle
damage, injury, or death could
occur. Always keep the
windshield, headlamps, and
camera sensors clean and in
good repair. Do not use LKA in (Continued)
Warning (Continued)
bad weather conditions or on
roads with unclear lane markings,
such as construction zones.
{Warning
Using LKA while towing a trailer
or on slippery roads could cause
loss of control of the vehicle and
a crash. Turn the system off.
How the System Works
LKA uses a camera sensor installed
on the windshield ahead of the
rearview mirror to detect lane
markings. It may provide brief
steering assist if it detects an
unintended lane departure. It may
further provide an audible alert or
driver seat may pulse indicating that
a lane marking has been crossed.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 259
Warning (Continued)
.Bring the fill nozzle in
contact with the inside of
the fill opening before
operating the nozzle.
Maintain contact until filling
is complete.
. Keep sparks, flames, and
smoking materials away
from fuel.
. Do not use electronic
devices while pumping fuel.
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 0363. To tow
the vehicle behind another vehicle
such as a motor home, see
Recreational Vehicle Towing 0364.
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

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
260 Driving and Operating
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. .
Vehicles can tow in D (Drive).
Tow/Haul Mode is recommended
for heavier trailers. See Tow/
Haul Mode 0218. If the
transmission downshifts too
often, a lower gear may be
selected using Manual Mode.
See Manual Mode 0216.
If equipped, the following driver
assistance features should be
turned off when towing a trailer:
. Adaptive Cruise Control (ACC)
. Super Cruise Control
. Lane Keep Assist (LKA)
. Park Assist
. Automatic Parking Assist (APA)
. Reverse Automatic
Braking (RAB)
If equipped, the following driver
assistance features should be
turned to alert or off when towing a
trailer:
. Automatic Emergency
Braking (AEB)
. Intelligent Brake Assist (IBA) .
Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert
(LCA), the LCA detection zones that
extend back from the side of the
vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic
Alert (RCTA), use caution while
backing up when towing a trailer, as
the RCTA detection zones that
extend out from the back of the
vehicle do not move further back
when a trailer is towed.
{Warning
When towing a trailer, exhaust
gases may collect at the rear of
the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
When towing a trailer: (Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 261
Warning (Continued)
.Do not drive with the
liftgate, trunk/hatch,
or rear-most window open.
. Fully open the air outlets on
or under the instrument
panel.
. Also adjust the climate
control system to a setting
that brings in only outside
air. See “Climate Control
Systems” in the Index.
For more information about
carbon monoxide, see Engine
Exhaust 0212.
Towing a trailer requires experience.
The combination of the vehicle and
trailer is longer and not as
responsive as the vehicle itself. Get
used to the handling and braking of
the combination by driving on a
level road surface before driving on
public roads. The trailer structure, the tires, and
the brakes must be all be rated to
carry the intended cargo.
Inadequate trailer equipment can
cause the combination to operate in
an unexpected or unsafe manner.
Before driving, inspect all trailer
hitch parts and attachments, safety
chains, electrical connectors, lamps,
tires, and mirrors. See
Towing
Equipment 0270. If the trailer has
electric brakes, start the
combination moving and then
manually apply the trailer brake
controller to check the trailer brakes
work. During the trip, occasionally
check that the cargo and trailer are
secure and that the lamps and any
trailer brakes are working.
Towing with a Stability Control
System
When towing, the stability control
system might be heard. The system
reacts to vehicle movement caused
by the trailer, which mainly occurs
during cornering. This is normal
when towing heavier trailers.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving without a trailer. This can
help to avoid heavy braking and
sudden turns.
Passing
More passing distance is needed
when towing a trailer. The
combination of the vehicle and
trailer will not accelerate as quickly
and is much longer than the vehicle
alone. It is necessary to go much
farther beyond the passed vehicle
before returning to the lane. Pass
on level roadways. Avoid passing
on hills if possible.
Backing Up
Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move that hand to
the left. To move the trailer to the
right, move that hand to the right.
Always back up slowly and,
if possible, have someone
guide you.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
262 Driving and Operating
Making TurnsCaution
Turn more slowly and make wider
arcs when towing a trailer to
prevent damage to your vehicle.
Making very sharp turns could
cause the trailer to contact the
vehicle.
Make wider turns than normal when
towing, so trailer will not go over soft
shoulders, over curbs, or strike road
signs, trees, or other objects.
Always signal turns well in advance.
Do not steer or brake suddenly.
Driving on Grades
Reduce speed and shift to a lower
gear before starting down a long or
steep downhill grade. If the
transmission is not shifted down, the
brakes may overheat and result in
reduced braking efficiency. The 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
0300.Parking on Hills
{Warning
To 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.