Black plate (73,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-73
{WARNING
Fuel can spray out on you if
you open the fuel cap too
quickly. If you spill fuel and then
something ignites it, you could
be badly burned. This spray can
happen if the tank is nearly full,
and is more likely in hot weather.
Open the fuel cap slowly and wait
for any hiss noise to stop. Then
unscrew the cap all the way.
Be careful not to spill fuel. Do not
top off or overfill the tank and
wait a few seconds after you have
finished pumping before removing
the nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care on page 10‑98. When replacing the fuel cap,
insert the tether in its hole before
tightening the cap. Turn the fuel cap
clockwise until it clicks. It will require
more effort to turn the fuel cap on
the last turn as you tighten it. Make
sure the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. See
Malfunction
Indicator Lamp on page 5‑21.
If the vehicle has a Driver
Information Center (DIC), the
TIGHTEN GAS CAP message
displays if the fuel cap is not
properly installed.
{WARNING
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel
by shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Notice: If a new fuel cap is
needed, be sure to get the right
type of cap from your dealer.
The wrong type of fuel cap might
not fit properly, might cause the
malfunction indicator lamp to
light, and could damage the fuel
tank and emissions system. See
Malfunction Indicator Lamp on
page 5‑21.
Black plate (74,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-74 Driving and Operating
Filling a Portable Fuel
Container
{WARNING
Never fill a portable fuel container
while it is in the vehicle. Static
electricity discharge from the
container can ignite the fuel
vapor. You can be badly burned
and the vehicle damaged if this
occurs. To help avoid injury to you
and others:
.Dispense fuel only into
approved containers.
.Do not fill a container while
it is inside a vehicle, in a
vehicle's trunk, pickup bed,
or on any surface other than
the ground.(Continued)
WARNING (Continued)
.Bring the fill nozzle in contact
with the inside of the fill
opening before operating the
nozzle. Contact should be
maintained until the filling is
complete.
.Do not smoke while
pumping fuel.
.Do not use a cellular phone
while pumping fuel.
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 for towing a trailer.
See the following trailer towing
information in this section:
.For information on driving
while towing a trailer, see
“Driving Characteristics and
Towing Tips.”
.For maximum vehicle and trailer
weights, see“Trailer Towing.”
.For information on equipment
to tow a trailer, see “Towing
Equipment.”
Black plate (76,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-76 Driving and Operating
Driving with a Trailer
{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.
Engine exhaust contains Carbon
Monoxide (CO) which cannot be
seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing
a trailer:
.Have the exhaust system
inspected for leaks and make
necessary repairs before
starting a trip.
.Never drive with the liftgate,
trunk/hatch, or rear-most
window open.(Continued)
WARNING (Continued)
.Fully open the air outlets
on or under the instrument
panel.
.Adjust the Climate Control
system to a setting that
brings in only outside air
and set the fan speed to the
highest setting. See Climate
Control System in the Index.
For more information about
Carbon Monoxide, see Engine
Exhaust on page 9‑36.
Towing a trailer requires a certain
amount of experience. The
combination you are driving is
longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road. Before starting, check all trailer
hitch parts and attachments, safety
chains, electrical connectors,
lamps, tires and mirrors. If the
trailer has electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle 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 will not accelerate
as quickly and is longer so it is
necessary to go much farther
beyond the passed vehicle before
returning to the lane.
Black plate (77,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-77
Backing Up
Hold the bottom of the steering
wheel with one hand. Then, to move
the trailer to the left, move that hand
to the left. To move the trailer to the
right, move your hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making Turns
Notice:Making very sharp turns
while trailering could cause the
trailer to come in contact with the
vehicle. The vehicle could be
damaged. Avoid making very
sharp turns while trailering.
When turning with a trailer, make
wider turns than normal. Do this
so the trailer will not strike soft
shoulders, curbs, road signs, trees
or other objects. Avoid jerky or
sudden maneuvers. Signal well in
advance. If the trailer turn signal bulbs burn
out, the arrows on the instrument
panel will still flash for turns. It is
important to check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a
lower gear
beforestarting down a
long or steep downgrade. If the
transmission is not shifted down,
the brakes might get hot and no
longer work well.
Vehicles 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. The tow/haul mode may be used if
the transmission shifts too often.
See
Tow/Haul Mode Light on
page 5‑25.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the
engine off. If the overheat warning
comes on, see Engine Overheating
on page 10‑21.
Black plate (78,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-78 Driving and Operating
Parking on Hills
{WARNING
Parking the vehicle on a hill
with the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig 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, release the regular brakes
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park).
5. If the vehicle is four-wheel-drive and has a two-speed transfer
case, be sure the transfer case
is in a drive gear and not in
N (Neutral).
6. Release the brake pedal.
{WARNING
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle
can roll. (Continued)
WARNING (Continued)
If the engine has been left
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when on fairly
level ground, use the steps that
follow.
Always put the shift lever fully in
P (Park) with the parking brake
firmly set.
If the transfer case on a
four-wheel-drive vehicle is in
N (Neutral), the vehicle will be
free to roll, even if the shift lever
is in P (Park). Be sure the transfer
case is in a drive gear —not in
N (Neutral).
Black plate (79,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-79
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine.
3. Shift into a gear.
4. Release the parking brake.
5. Let up on the brake pedal.
6. Drive slowly until the trailer isclear of the chocks.
7. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule or
Index for more information. Things
that are especially important in
trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system and
brake system. It is a good idea to
inspect these before and during
the trip. Check periodically to see that all
hitch nuts and bolts are tight.
Trailer Towing
If the vehicle has a hybrid engine,
see the Hybrid supplement for more
information.
Do not tow a trailer during break‐in.
See
New Vehicle Break-In on
page 9‑28 for more information.
{WARNING
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
For example, if the trailer is
too heavy, the brakes may not
work well—or even at all. The
driver and passengers could be
seriously injured. The vehicle may
also be damaged; the resulting
repairs would not be covered by
the vehicle warranty. Pull a trailer
(Continued)
WARNING (Continued)
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.
Notice: Pulling a trailer
improperly can damage the
vehicle and result in costly
repairs not covered by the
vehicle warranty. To pull a trailer
correctly, follow the advice in this
section and see your dealer for
important information about
towing a trailer with the vehicle.
To identify the trailering capacity of
the vehicle, read the information in
“Weight of the Trailer” that appears
later in this section.
Black plate (88,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-88 Driving and Operating
This symbol is located on the Trailer
Brake Control Panel on vehicles
with an Integrated Trailer Brake
Control System. The power output
to the trailer brakes is based on the
amount of brake pressure being
applied by the vehicle’s brake
system. 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
the StabiliTrak system. If the vehicle’s brake, anti‐lock
brake or StabiliTrak systems are
not functioning properly, the ITBC
system may not be fully functional
or may not function at all. Make
sure all of these systems are
fully operational to ensure full
functionality of the ITBC system.
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 or
in RUN.
The ITBC system can only be used
with trailers with electric brakes.{WARNING
Connecting a trailer that is not
compatible with the ITBC system
may result in reduced or complete
loss of trailer braking. There
may be an increase in stopping
distance or trailer instability which
could result in personal injury or
damage to the vehicle, trailer,
or other property. An aftermarket
controller may be available for
use with trailers with surge,
air, or electric‐over‐hydraulic
trailer brake systems. To
determine the type of brakes
on the trailer and the availability
of controllers, check with your
trailer manufacturer or dealer.
Black plate (90,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-90 Driving and Operating
The Trailer Brake Display Page can
be displayed by performing any of
the following actions:
.Scrolling through the DIC
menu pages using the odometer
trip stem or the DIC Vehicle
Information button (if equipped).
.Pressing a Trailer Gain
button–If the Trailer Brake
Display Page is not currently
displayed, pressing a Trailer
Gain button will first recall the
current Trailer Gain setting.
After the Trailer Brake Display
Page is displayed, each press
and release of the gain buttons
will then cause the Trailer Gain
setting to change.
.Activating the Manual Trailer
Brake Apply lever
.Connecting a trailer equipped
with electric trailer brakes All DIC warning and service
messages must first be
acknowledged by the driver
by pressing the odometer trip
stem or the DIC Vehicle Information
button (if equipped) before the
Trailer Brake Display Page can be
displayed and Trailer Gain can be
adjusted.
TRAILER GAIN
–This setting is
displayed anytime the Trailer Brake
Display Page is active. This setting
can be adjusted from 0.0 to 10.0
with either a trailer connected or
disconnected. To adjust the Trailer
Gain, press one of the Trailer Gain
adjustment buttons located on the
Trailer Brake Control Panel. Press
and hold a gain button to cause the
Trailer Gain to continuously adjust.
To turn the output to the trailer off,
adjust the Trailer Gain setting to
0.0 (zero).
0.0 (zero) gain is the factory
default setting. To properly adjust
trailer gain, see the Trailer Gain
Adjustment Procedure later in this
section. TRAILER OUTPUT
–This is
displayed any time a trailer with
electric brakes is connected.
Output to the electric brakes is
based on the amount of vehicle
braking present and relative to
the Trailer Gain setting. Output is
displayed from 0 to 10 bars for each
gain setting.
The Trailer Output will
indicate “- - - - - -“ on the
Trailer Brake Display Page
whenever the following occur:
.No trailer is connected.
.A trailer without electric brakes
is connected (no DIC message
is displayed).
.A trailer with electric brakes
has become disconnected
(a CHECK TRAILER WIRING
message will also be displayed
on the DIC).