towing GMC YUKON XL 2018 Owner's Guide

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 269Pressing this button at the end of
the shift lever turns on and off the
Tow/Haul Mode.
This indicator light on the instrument
cluster comes on when the Tow/
Haul Mode is on.
Tow/Haul is a feature that assists
when pulling a heavy trailer or a
large or heavy load. See Tow/Haul
Mode 0 222 .
Tow/Haul 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 “ Weight of the Trailer ” under
Trailer Towing 0 262 . Tow/Haul is
most useful under the following
driving conditions:
.
When pulling a heavy trailer or a
large or heavy load through
rolling terrain. .
When pulling a heavy trailer or a
large or heavy load in
stop-and-go traffic.
.
When pulling a heavy trailer or a
large or heavy load in busy
parking lots where improved low
speed control of the vehicle is
desired.
Operating the vehicle in Tow/Haul
when lightly loaded or with no trailer
at all will not cause damage.
However, there is no benefit to the
selection of Tow/Haul when the
vehicle is unloaded. Such a
selection when unloaded may result
in unpleasant engine and
transmission driving characteristics
and reduced fuel economy. Tow/
Haul is recommended only when
pulling a heavy trailer or a large or
heavy load. 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
brakes.
This symbol is on the Trailer Brake
Control Panel on vehicles with an
ITBC system. The power output to
the trailer brakes is based on the
amount of brake pressure being
applied by the vehicle ’ s brake
system, and on the type of trailer
brakes detected. 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, antilock brake,
and StabiliTrak systems. In trailering
conditions that cause the vehicle ’ s

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
272 Driving and Operating To adjust Trailer Gain for each
towing condition:
1. Drive the vehicle with the trailer
attached on a level road
surface representative of the
towing condition and free of
traffic at about 32 to 40 km/h
(20 to 25 mph) and fully apply
the Manual Trailer Brake apply
lever.
Adjusting Trailer Gain at
speeds lower than 32 to
40 km/h (20 to 25 mph) may
result in an incorrect gain
setting.
2. Adjust the Trailer Gain, using
the Trailer Gain adjustment
buttons, to just below the point
of trailer wheel lock-up,
indicated by trailer wheel
squeal or tire smoke when a
trailer wheel locks.
Trailer wheel lock-up may not
occur if towing a heavily loaded
trailer. In this case, adjust the
Trailer Gain to the highest
allowable setting for the towing
condition. 3. Readjust Trailer Gain any time
vehicle loading, trailer loading,
or road surface conditions
change or if trailer wheel
lock-up is noticed at any time
while towing.
Other ITBC-Related DIC Messages
In addition to displaying TRAILER
GAIN and OUTPUT through the
DIC, trailer connection and ITBC
system status are displayed on
the DIC.
TRAILER CONNECTED: This
message will briefly display when a
trailer with electric brakes is first
connected to the vehicle. This
message will automatically turn off
in about 10 seconds. This message
can be acknowledged before it
automatically turns off.
CHECK TRAILER WIRING: This
message will display if:
.
The ITBC system first
determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected from the vehicle. If the disconnect occurs while
the vehicle is stationary, this
message will automatically turn
off in about 30 seconds. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
If the disconnect occurs while
the vehicle is moving, this
message will continue until the
ignition is turned off. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
.
There is an electrical fault in the
wiring to the trailer brakes. This
message will continue as long
as there is an electrical fault in
the trailer wiring. This message
will also turn off if it is
acknowledged.
To determine if the electrical fault is
on the vehicle side or trailer side of
the trailer wiring harness
connection:
1. Disconnect the trailer wiring
harness from the vehicle.
2. Turn the ignition off.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 277When It Is Time for New
Tires . . . . . . . . . . . . . . . . . . . . . . . . 335
Buying New Tires . . . . . . . . . . . . . 335
Different Size Tires and
Wheels . . . . . . . . . . . . . . . . . . . . . . 337
Uniform Tire Quality
Grading . . . . . . . . . . . . . . . . . . . . . 337
Wheel Alignment and Tire
Balance . . . . . . . . . . . . . . . . . . . . . 339
Wheel Replacement . . . . . . . . . . 339
Tire Chains . . . . . . . . . . . . . . . . . . . 340
If a Tire Goes Flat . . . . . . . . . . . . 341
Tire Changing . . . . . . . . . . . . . . . . 342
Full-Size Spare Tire . . . . . . . . . . 350
Jump Starting Jump Starting - North
America . . . . . . . . . . . . . . . . . . . . . 351
Towing the Vehicle Towing the Vehicle . . . . . . . . . . . 355
Recreational Vehicle
Towing . . . . . . . . . . . . . . . . . . . . . . 355
Appearance Care Exterior Care . . . . . . . . . . . . . . . . . 360
Interior Care . . . . . . . . . . . . . . . . . . 364
Floor Mats . . . . . . . . . . . . . . . . . . . . 367 General Information For service and parts needs, visit
your dealer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one of
these marks:
California Proposition
65 Warning
{ WarningMost motor vehicles, including
this one, as well as many of its
service parts and fluids, contain
and/or emit chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Engine
exhaust, many parts and
systems, many fluids, and some
component wear by-products
contain and/or emit these
chemicals. For more information
go to www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0 298
and Jump Starting - North America
0 351 and the back cover.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 295If Steam is Coming from the
Engine Compartment
{ WarningSteam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure
cap, even a little, can cause them
to come out at high speed and
you could be burned. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to cool.
If No Steam is Coming from
the Engine Compartment The ENGINE OVERHEATED STOP
ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious
problem. If there is an engine overheat
warning, but no steam is seen or
heard, the problem may not be too
serious. Sometimes the engine can
get a little too hot when the vehicle:
.
Climbs a long hill on a hot day.
.
Stops after high-speed driving.
.
Idles for long periods in traffic.
.
Tows a trailer; see Trailer Towing
0 262 .
If the ENGINE OVERHEATED
STOP ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message appears with no sign of
steam, try this for a minute or so:
1. Turn the air conditioning off.
2. Turn the heater on to the
highest temperature and to the
highest fan speed. Open the
windows as necessary.
3. When it is safe to do so, pull off
the road, shift to P (Park) or
N (Neutral), and let the
engine idle.
If the engine coolant temperature
gauge is no longer in the overheat
zone or an overheat warning no longer displays, the vehicle can be
driven. Continue to drive the vehicle
slowly for about 10 minutes. Keep a
safe vehicle distance from the
vehicle in front. If the warning does
not come back on, continue to drive
normally and have the cooling
system checked for proper fill and
function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is still no sign of steam and
the vehicle is equipped with an
engine driven cooling fan, push
down the accelerator until the
engine speed is about twice as fast
as normal idle speed for at least
five minutes while the vehicle is
parked. If the warning is still there,
turn off the engine and get everyone
out of the vehicle until it cools down.
If there is no sign of steam, idle the
engine for five minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
296 Vehicle Care
Engine Fan If the vehicle has electric cooling
fans, the fans may be heard
spinning at low speed during most
everyday driving. The fans may turn
off if no cooling is required. Under
heavy vehicle loading, trailer towing,
high outside temperatures,
or operation of the air conditioning
system, the fans may change to
high speed and an increase in fan
noise may be heard. This is normal
and indicates that the cooling
system is functioning properly. The
fans will change to low speed when
additional cooling is no longer
required.
The electric engine cooling fans
may run after the engine has been
turned. off. This is normal and no
service is required.
Washer Fluid What to Use
When windshield washer fluid needs
to be added, be sure to read the
manufacturer's instructions before
use. Use a fluid that has sufficient protection against freezing in an
area where the temperature may fall
below freezing.
Adding Washer Fluid The vehicle has a low washer fluid
message on the DIC that comes on
when the washer fluid is low. The
message is displayed for
15 seconds at the start of each
ignition cycle. When the WASHER
FLUID LOW ADD FLUID message
displays, washer fluid will need to
be added to the windshield washer
fluid reservoir.
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. See Engine
Compartment Overview 0 280 for
reservoir location. Caution .
Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
.
Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
.
Do not mix water with
ready-to-use washer fluid.
Water can cause the
solution to freeze and
damage the washer fluid
tank and other parts of the
washer system.
.
When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
.
Fill the washer fluid tank
only three-quarters full when
it is very cold. This allows
for fluid expansion if
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 355Jumper Cable Removal
Reverse the sequence exactly when
removing the jumper cables.
After starting the disabled vehicle
and removing the jumper cables,
allow it to idle for several minutes.
Towing the Vehicle CautionIncorrectly towing a disabled
vehicle may cause damage. The
damage would not be covered by
the vehicle warranty.
Do not lash or hook to
suspension components. Use the
proper straps around the tires to
secure the vehicle.
Use only a flatbed tow truck for
towing a disabled vehicle. Never
use a sling type lift or damage will
occur. Use ramps to help reduce
approach angles if necessary.
A towed vehicle should have its
drive wheels off the ground.
Consult a professional towing
service if the disabled vehicle must
be towed. Front Attachment Points
The vehicle is equipped with
specific attachment points to be
used to pull the vehicle onto a
flatbed car carrier from a flat road
surface. Do not use these
attachment points to pull the vehicle
from snow, mud or sand.
Recreational Vehicle
Towing Recreational vehicle towing means
towing the vehicle behind another
vehicle, such as a motor home. The
two most common types of
recreational vehicle towing are

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
356 Vehicle Care dinghy and dolly towing. Dinghy
towing is towing the vehicle with all
four wheels on the ground. Dolly
towing is towing the vehicle with two
wheels on the ground and two
wheels on a dolly.
Follow the tow vehicle
manufacturer ’ s instructions. See
your dealer or trailering professional
for additional advice and equipment
recommendations.
CautionUse of a shield mounted in front
of the vehicle grille could restrict
airflow and cause damage to the
transmission. The repairs would
not be covered by the vehicle
warranty. If using a shield, only
use one that attaches to the
towing vehicle. Dinghy Towing Two-Wheel-Drive Vehicles
CautionIf the two-wheel-drive vehicle is
towed with all four wheels on the
ground, the drivetrain
components could be damaged.
The repairs would not be covered
by the vehicle warranty.
Two-wheel-drive vehicles should not
be towed with all four wheels on the
ground. Four-Wheel-Drive Vehicles
Only dinghy tow four-wheel-drive
vehicles with a two speed transfer
case that have a N (Neutral) and a 4
n setting.
{ Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or others could
be injured. Set the parking brake
before shifting the transfer case
to N (Neutral).

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
358 Vehicle Care 5. Turn the ignition to ON/RUN
with the engine off. Shift the
transfer case out of N (Neutral)
to 2
m . See “ Shifting out of
N (Neutral) ” under Four-Wheel
Drive 0 222 . See your dealer if
the transfer case cannot be
shifted out of N (Neutral).
6. Check that the vehicle is in 2
mby starting the engine and
shifting the transmission to
R (Reverse) and then to D
(Drive). There should be
movement of the vehicle while
shifting.
7. Shift the transmission to
P (Park) and turn off the
ignition.
8. Disconnect the vehicle from the
tow vehicle.
9. Release the parking brake.
10. Reset any lost presets.
The outside temperature
display will default to 0 °C
(32 °F) but will reset with
normal usage. Dolly Towing – Front Towing
(Front Wheels Off the Ground)
CautionIf a two-wheel-drive vehicle is
towed with the rear wheels on the
ground, the transmission could be
damaged. The repairs would not
be covered by the vehicle
warranty. Never tow the vehicle
with the rear wheels on the
ground. CautionTowing a four-wheel-drive vehicle
with all four wheels on the
ground, or even with only two of
its wheels on the ground, will
damage drivetrain components.
Do not tow a four-wheel-drive
vehicle with any of its wheels on
the ground.
This vehicle should not be towed
with the rear wheels on the ground.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 359Dolly Towing – Rear Towing
(Rear Wheels Off the
Ground) – Four-Wheel-Drive
Vehicles
Caution
Towing a four-wheel-drive vehicle
with all four wheels on the
ground, or even with only two of
its wheels on the ground, will
damage drivetrain components.
Do not tow a four-wheel-drive
vehicle with any of its wheels on
the ground. This vehicle should not be towed
with any wheels on the ground.
Dolly Towing – Rear Towing
(Rear Wheels Off the
Ground) – Two-Wheel-Drive
Vehicles
To dolly tow the vehicle from
the rear:
1. Attach the dolly to the tow
vehicle following the dolly
manufacturer's instructions.
2. Drive the rear wheels onto the
dolly.
3. Firmly set the parking brake.
See Parking Brake 0 228 . 4. Put the transmission in
P (Park).
5. Secure the vehicle to the dolly
following the manufacturer's
instructions.
6. Use an adequate clamping
device designed for towing to
ensure that the front wheels
are locked into the straight
position.
7. Turn the ignition to LOCK/OFF.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
370 Service and Maintenance have your dealer perform these
services every 12 000 km/7,500 mi.
Proper vehicle maintenance helps to
keep the vehicle in good working
condition, improves fuel economy,
and reduces vehicle emissions.
Because of the way people use
vehicles, maintenance needs vary.
There may need to be more
frequent checks and services. The
Additional Required Services -
Normal are for vehicles that:
.
Carry passengers and cargo
within recommended limits on
the Tire and Loading Information
label. See Vehicle Load Limits
0 200 .
.
Are driven on reasonable road
surfaces within legal driving
limits.
.
Use the recommended fuel. See
Fuel 0 254 .
Refer to the information in the
Maintenance Schedule Additional
Required Services - Normal chart.
The Additional Required Services -
Severe are for vehicles that are: .
Mainly driven in heavy city traffic
in hot weather
.
Mainly driven in hilly or
mountainous terrain
.
Frequently towing a trailer
.
Used for high speed or
competitive driving
.
Used for taxi, police, or delivery
service
Refer to the information in the
Maintenance Schedule Additional
Required Services - Severe chart.
{ WarningPerforming maintenance work can
be dangerous and can cause
serious injury. Perform
maintenance work only if the
required information, proper tools,
and equipment are available.
If they are not, see your dealer to
have a trained technician do the
work. See Doing Your Own
Service Work 0 278 .Maintenance
Schedule Owner Checks and Services At Each Fuel Stop
.
Check the engine oil level. See
Engine Oil 0 283 .
Once a Month
.
Check the tire inflation
pressures. See Tire Pressure
0 327 .
.
Inspect the tires for wear. See
Tire Inspection 0 333 .
.
Check the windshield washer
fluid level. See Washer Fluid
0 296 .
Engine Oil Change When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km/600 mi. If driven
under the best conditions, the
engine oil life system may not
indicate the need for vehicle service
for up to a year. The engine oil and
filter must be changed at least once