GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 273
Trailer Brakes
Loaded trailers over 900 kg
(2,000 lb) must be equipped with
brake systems and with brakes for
each axle. Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may
require trailers to have their own
braking system if the loaded weight
of the trailer exceeds certain
minimums that can vary from state
to state. Read and follow the
instructions for the trailer brakes so
they are installed, adjusted, and
maintained properly. Never attempt
to tap into your vehicle's hydraulic
brake system. If you do, both the
vehicle anti-lock brakes and the
trailer brakes may not function,
which could result in a crash.
Trailer Wiring Harness
The seven-pin trailer connector is
mounted in the bumper. This
connector can be plugged into aseven-pin universal heavy-duty
trailer connector available through
your dealer.
Use only a round, seven-wire
connector with flat blade terminals
meeting SAE J2863 specifications
for proper electrical connectivity.
The seven-wire harness contains
the following trailer circuits:
.
Yellow/Grey: Left Stop/Turn
Signal
. Green/Violet: Right Stop/Turn
Signal
. Grey/Brown: Taillamps
. White: Ground
. White/Green: Back-up Lamps
. Red/Green: Battery Feed
. Dark Blue: Trailer Brake
To help charge a remote
(non-vehicle) battery, press the Tow/
Haul Mode button at the end of the
shift lever. If the trailer is too light for
Tow/Haul Mode, turn on the
headlamps to help charge the
battery.
Electric Brake Control Wiring
Provisions
These wiring provisions are
included with the vehicle as part of
the trailer wiring package. These
provisions are for an electric brake
controller.
The harness should be installed 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.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals should will illuminate to
indicate the vehicle is turning,
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
274 Driving and Operating
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, seeTow/Haul
Mode 0218.
Tow/Haul assists when pulling a
heavy trailer or a large or
heavy load.
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
Combined Weight Rating (GCWR).
See “Maximum Trailer Weight”
under Trailer Towing 0264.
Tow/Haul Mode is most useful when
towing a heavy trailer or carrying a
large or heavy load:
. through rolling terrain
. in stop-and-go traffic
. in busy parking lots Operating the vehicle in Tow/Haul
Mode when lightly loaded or not
towing will not cause damage;
however, it is not recommended and
may result in unpleasant engine and
transmission driving characteristics
and reduced fuel economy.Integrated Trailer Brake
Control System
The vehicle may have an Integrated
Trailer Brake Control (ITBC) system
for use with electric trailer brakes or
most electric over hydraulic trailer
brake systems. These instructions
apply to both types of electric trailer
brakes.
This symbol is on the Trailer Brake
Control Panel on vehicles with an
ITBC system. The power output to
the trailer brakes is proportional to
the amount of vehicle braking. This
available power output to the trailer
brakes can be adjusted to a wide
range of trailering situations.
The ITBC system is integrated with
the vehicle’
s brake, anti-lock brake,
and StabiliTrak systems. In trailering
conditions that cause the vehicle’s
anti-lock brake or StabiliTrak
systems to activate, power sent to
the trailer's brakes will be
automatically adjusted to minimize
trailer wheel lock-up. This does not
imply that the trailer has StabiliTrak.
If the vehicle’s brake, anti-lock
brake, or StabiliTrak systems are
not functioning properly, the ITBC
system may not function fully or at
all. Make sure all of these systems
are fully operational to allow the
ITBC system to function properly.
The ITBC system is powered
through the vehicle's electrical
system. Turning the ignition off will
also turn off the ITBC system. The
ITBC system is fully functional only
when the ignition is in ON/RUN.
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
Driving and Operating 279
the vehicle’s trailer brake systems
or other systems, including
integrated anti-sway systems,
if equipped. Messages related to
trailer connections or trailer brakes
could appear on the DIC. The
effects of these aftermarket devices
on vehicle handling or trailer brake
performance is not known.
{Warning
Use of aftermarket electronic
trailer sway control devices could
result in reduced trailer brake
performance, loss of trailer
brakes, or other malfunctions, and
result in a crash. You or others
could be seriously injured or
killed. Before using one of these
devices:
. Ask the device or trailer
manufacturer if the device
has been thoroughly tested
for compatibility with the
make, model, and year of
(Continued)
Warning (Continued)
your vehicle and any
optional equipment installed
on your vehicle.
. Before driving, check the
trailer brakes are working
properly, if equipped. Drive
the vehicle with the trailer
attached on a level road
surface that is free of traffic
at about 32-40 km/h
(20-25 mph) and fully apply
the manual trailer brake
apply lever. Also, check the
trailer brake lamps and
other lamps are functioning
correctly.
. If the trailer brakes are not
operating properly at any
time, or if a DIC message
indicates problems with the
trailer connections or trailer
brakes, carefully pull the
vehicle over to the side of
the road when traffic
conditions allow.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are
designed with stiff sidewalls to help
prevent sway and to support heavy
loads. These features can make it
difficult to determine if the trailer tire
pressures are low only based on a
visual inspection.
Always check all trailer tire
pressures before each trip when the
tires are cool. Low trailer tire
pressure is a leading cause of trailer
tire blow-outs.
Trailer tires deteriorate over time.
The trailer tire sidewall will show the
week and year the tire was
manufactured. Many trailer tire
manufacturers recommend
replacing tires more than six
years old.
Overloading is another leading
cause of trailer tire blow-outs. Never
load your trailer with more weight
than the tires are designed to
support. The load rating is located
on the trailer tire sidewall.
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
332 Vehicle Care
Light Truck (LT-Metric) Tire:A
tire used on light duty trucks and
some multipurpose passenger
vehicles.
Load Index
:An assigned
number ranging from 1 to 279
that corresponds to the load
carrying capacity of a tire.
Maximum Inflation Pressure
:
The maximum air pressure to
which a cold tire can be inflated.
The maximum air pressure is
molded onto the sidewall.
Maximum Load Rating
:The
load rating for a tire at the
maximum permissible inflation
pressure for that tire.
Maximum Loaded Vehicle
Weight
:The sum of curb
weight, accessory weight,
vehicle capacity weight, and
production options weight. Normal Occupant Weight
:The
number of occupants a vehicle
is designed to seat multiplied by
68 kg (150 lb). See Vehicle Load
Limits 0196.
Occupant Distribution
:
Designated seating positions.
Outward Facing Sidewall
:The
side of an asymmetrical tire that
has a particular side that faces
outward when mounted on a
vehicle. The side of the tire that
contains a whitewall, bears
white lettering, or bears
manufacturer, brand, and/or
model name molding that is
higher or deeper than the same
moldings on the other sidewall
of the tire.
Passenger (P-Metric) Tire
:A
tire used on passenger cars and
some light duty trucks and
multipurpose vehicles.
Recommended Inflation
Pressure
:Vehicle
manufacturer's recommended tire inflation pressure as shown
on the tire placard. See
Tire
Pressure 0333 and
Vehicle Load Limits 0196.
Radial Ply Tire
:A pneumatic
tire in which the ply cords that
extend to the beads are laid at
90 degrees to the centerline of
the tread.
Rim
:A metal support for a tire
and upon which the tire beads
are seated.
Sidewall
:The portion of a tire
between the tread and the bead.
Speed Rating
:An
alphanumeric code assigned to
a tire indicating the maximum
speed at which a tire can
operate.
Traction
:The friction between
the tire and the road surface.
The amount of grip provided.
Tread
:The portion of a tire that
comes into contact with
the road.
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-13566587) - 2020 - CRC - 4/15/19
404 Customer Information
Insuring the Vehicle
Protect your investment in the GM
vehicle with comprehensive and
collision insurance coverage. There
are significant differences in the
quality of coverage afforded by
various insurance policy terms.
Many insurance policies provide
reduced protection to the GM
vehicle by limiting compensation for
damage repairs through the use of
aftermarket collision parts. Some
insurance companies will not
specify aftermarket collision parts.
When purchasing insurance, we
recommend that you ensure that the
vehicle will be repaired with GM
original equipment collision parts.
If such insurance coverage is not
available from your current
insurance carrier, consider switching
to another insurance carrier.
If the vehicle is leased, the leasing
company may require you to have
insurance that ensures repairs with
Genuine GM Original Equipment
Manufacturer (OEM) parts or
Genuine Manufacturer replacementparts. Read the lease carefully, as
you may be charged at the end of
the lease for poor quality repairs.
If a Crash Occurs
If there has been an injury, call
emergency services for help. Do not
leave the scene of a crash until all
matters have been taken care of.
Move the vehicle only if its position
puts you in danger, or you are
instructed to move it by a police
officer.
Give only the necessary information
to police and other parties involved
in the crash.
For emergency towing see
Roadside Assistance Program
0
400.
Gather the following information:
. Driver name, address, and
telephone number
. Driver license number
. Owner name, address, and
telephone number
. Vehicle license plate number .
Vehicle make, model, and
model year
. Vehicle Identification
Number (VIN)
. Insurance company and policy
number
. General description of the
damage to the other vehicle
Choose a reputable repair facility
that uses quality replacement parts.
See “Collision Parts” earlier in this
section.
If the airbag has inflated, see What
Will You See after an Airbag
Inflates? 078.
Managing the Vehicle Damage
Repair Process
In the event that the vehicle requires
damage repairs, GM recommends
that you take an active role in its
repair. If you have a pre-determined
repair facility of choice, take the
vehicle there, or have it towed there.
Specify to the facility that any
required replacement collision parts
be original equipment parts, either
new Genuine GM parts or recycled
GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-13566587) - 2020 - CRC - 4/15/19
Index 427
Lighting (cont'd)LED . . . . . . . . . . . . . . . . . . . . . . . . . . 312
Lights Airbag Readiness . . . . . . . . . . . . . 134
Antilock Brake System
(ABS) Warning . . . . . . . . . . . . . . 138
Brake System Warning . . . . . . . 138
Charging System . . . . . . . . . . . . . 135
Check Engine (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . 136
Cruise Control . . . . . . . . . . . . . . . . 144
Door Ajar . . . . . . . . . . . . . . . . . . . . . 144
Engine Coolant Temperature Warning . . . . . . . 141
Engine Oil Pressure . . . . . . . . . . 142
Flash-to-Pass . . . . . . . . . . . . . . . . . 167
Four-Wheel-Drive . . . . . . . . . . . . . 139
Front Fog Lamp . . . . . . . . . . . . . . 143
High-Beam On . . . . . . . . . . . . . . . . 143
High/Low Beam Changer . . . . . 166
Lane Keep Assist . . . . . . . . . . . . . 139
Low Fuel Warning . . . . . . . . . . . . 142
Seat Belt Reminders . . . . . . . . . . 133
Security . . . . . . . . . . . . . . . . . . . . . . 143
StabiliTrak OFF . . . . . . . . . . . . . . . 140
Tire Pressure . . . . . . . . . . . . . . . . . 141
Tow/Haul Mode . . . . . . . . . . . . . . . 139 Lights (cont'd)
Traction Control System
(TCS)/StabiliTrak . . . . . . . . . . . . 141
Traction Off . . . . . . . . . . . . . . . . . . . 140
Lock Steering Column . . . . . . . . . . . . . . . . 35
Locking Rear Axle . . . . . . . . . . . . . . 229
Locks Automatic Door . . . . . . . . . . . . . . . . . 25
Delayed Locking . . . . . . . . . . . . . . . . 25
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Lockout Protection . . . . . . . . . . . . . . 26
Power Door . . . . . . . . . . . . . . . . . . . . . 25
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Loss of Control . . . . . . . . . . . . . . . . . 187
Low Fuel Warning Light . . . . . . . . . 142
Low-Profile Tires . . . . . . . . . . . . . . . . 328
Lower Anchors and Tethers for Children (LATCH
System) . . . . . . . . . . . . . . . . . . . . . . . . 93
Lumbar Adjustment . . . . . . . . . . . . . . 49 Front Seats . . . . . . . . . . . . . . . . . . . . . 49
M
Magnetic Ride Control . . . . . . . . . . 229
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . 391 Maintenance and Care
Additional . . . . . . . . . . . . . . . . . . . . . 385
Maintenance Schedule . . . . . . . . . 379 Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . 388
Transfer Case . . . . . . . . . . . . . . . . 219
Malfunction Indicator Lamp . . . . . 136
Manual Mode . . . . . . . . . . . . . . . . . . . 216
Memory Seats . . . . . . . . . . . . . . . . . . . 51
Messages Engine Power . . . . . . . . . . . . . . . . 151
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 151
Vehicle Speed . . . . . . . . . . . . . . . . 152
Mirror Child-View . . . . . . . . . . . . . . . . . . . . . . 41
Mirrors
Automatic Dimming . . . . . . . . . . . . . 39
Automatic DimmingRearview . . . . . . . . . . . . . . . . . . . . . . 41
Blind Spot . . . . . . . . . . . . . . . . . . . . . . 39
Convex . . . . . . . . . . . . . . . . . . . . . . . . . 37
Folding . . . . . . . . . . . . . . . . . . . . . . . . . 38
Heated . . . . . . . . . . . . . . . . . . . . . . . . . 39
Manual Rearview . . . . . . . . . . . . . . . 41
Power . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Tilt in Reverse . . . . . . . . . . . . . . . . . . 40
Mirrors, Interior Rearview . . . . . . . . 41