light GMC YUKON XL 2011 Owners Manual

Black plate (46,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-46 Driving and Operating
To shift to the Four-Wheel Drive
Low position, the ignition must be in
ON/RUN and the vehicle must be
stopped or moving less than 5 km/h
(3 mph) with the transmission in
N (Neutral). The preferred method
for shifting into Four-Wheel Drive
Low is to have the vehicle moving
1.6 to 3.2 km/h (1 to 2 mph). Turn
the knob to the Four-Wheel Drive
Low position. You must wait for the
Four-Wheel Drive Low indicator
light to stop flashing and remain on
before shifting the transmission
into gear.
Notice:Shifting the transmission
into gear before the Four-Wheel
Drive Low indicator light has
stopped flashing could damage
the transfer case. To help avoid
damaging the vehicle, always wait
for the Four-Wheel Drive Low
indicator light to stop flashing
before shifting the transmission
into gear. The vehicle may have significant
engagement noise and bump when
shifting between Four-Wheel Drive
Low and Four-Wheel Drive High
ranges or from N (Neutral) while the
engine is running.
If the knob is turned to the
Four-Wheel Drive Low position
when the vehicle is in gear and/or
moving more than 1.6 to 3.2 km/h
(1 to 2 mph), the Four-Wheel Drive
Low indicator light will flash for
30 seconds and not complete the
shift. After 30 seconds the transfer
case will shift to Four-Wheel Drive
High mode. With the vehicle moving
less than 5 km/h (3 mph) and the
transmission in N (Neutral), attempt
the shift again.
Shifting Out of Four-Wheel
Drive Low
To shift from Four-Wheel Drive
Low to Four-Wheel Drive High,
AUTO, or Two-Wheel Drive High,
the vehicle must be stopped or
moving less than 5 km/h (3 mph)
with the transmission in N (Neutral)and the ignition in ON/RUN. The
preferred method for shifting out of
Four-Wheel Drive Low is to have
your vehicle moving 1.6 to 3.2 km/h
(1 to 2 mph). Turn the knob to the
Four-Wheel Drive High, AUTO,
or Two-Wheel Drive High position.
You must wait for the Four-Wheel
Drive High, AUTO, or Two-Wheel
Drive High indicator light to stop
flashing and remain on before
shifting the transmission into gear.
Notice:
Shifting the transmission
into gear before the Four-Wheel
Drive Low indicator light has
stopped flashing could damage
the transfer case. To help avoid
damaging the vehicle, always wait
for the Four-Wheel Drive Low
indicator light to stop flashing
before shifting the transmission
into gear.
The vehicle may have significant
engagement noise and bump when
shifting between Four-Wheel Drive
Low and Four-Wheel Drive High
ranges or from N (Neutral) while the
engine is running.

Black plate (47,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-47
If the knob is turned to the
Four-Wheel Drive High, AUTO,
or Two-Wheel Drive High switch
position when the vehicle is in
gear and/or moving more than
1.6 to 3.2 km/h (1 to 2 mph), the
Four-Wheel Drive High, AUTO or
Two-Wheel Drive High indicator light
will flash for 30 seconds but will not
complete the shift. With the vehicle
moving less than 5 km/h (3 mph)
and the transmission is in
N (Neutral), attempt the shift again.
Shifting into Neutral
To shift the transfer case to
N (Neutral) do the following:
1. Make sure the vehicle is parkedso that it will not roll.
2. Set the parking brake and apply the regular brake pedal. See
Parking Brake on page 9‑51 for
more information. 3. Start the vehicle or turn the
ignition to ON/RUN.
4. Put the transmission in N (Neutral).
5. Shift the transfer case to Two-Wheel Drive High.
6. Turn the transfer case dial clockwise to N (Neutral) until
it stops and hold it there until
the N (Neutral) light starts
blinking. This will take at least
10 seconds. Then slowly release
the dial to the Four‐Wheel Drive
Low position. The N (Neutral)
light will come on when the
transfer case shift to N (Neutral)
is complete.
7. If the engine is running, verify that the transfer case is in
N (Neutral) by shifting the
transmission to R (Reverse)
for one second, then shift the
transmission to D (Drive) for
one second. 8. Turn the ignition to ACC/
ACCESSORY, which will turn the
engine off.
9. Place the transmission shift lever in P (Park).
10. Release the parking brake prior to moving the vehicle.
11. Turn the ignition to LOCK/OFF.
Shifting Out of Neutral
To shift out of N Neutral do the
following:
1. Set the parking brake and apply the regular brake pedal.
2. Turn the ignition to ON/RUN with the engine off, and shift the
transmission to N (Neutral).
3. Turn the transfer case dial to the desired transfer case shift
position (Two-Wheel Drive
High, Four-Wheel Drive High,
or AUTO).
After the transfer case has
shifted out of N (Neutral), the
N (Neutral) light will go out.

Black plate (48,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-48 Driving and Operating
4. Release the parking brake priorto moving the vehicle.
Notice: Shifting the transmission
into gear before the Four-Wheel
Drive Low indicator light has
stopped flashing could damage
the transfer case. To help avoid
damaging the vehicle, always wait
for the Four-Wheel Drive Low
indicator light to stop flashing
before shifting the transmission
into gear.
5. Start the engine and shift the transmission to the desired
position.
Excessively shifting the transfer
case into or out of the different
modes may cause the transfer case
to enter the shift protection mode.
This will protect the transfer case
from possible damage and will only
allow the transfer case to respond
to one shift per 10 seconds. The
transfer case may stay in this mode
for up to three minutes.Four-Wheel Drive
(Single Speed Automatic
Transfer Case)
If the vehicle has four-wheel drive,
you can send the engine's driving
power to all four wheels for extra
traction. Read the following before
using four-wheel drive.
Notice: Driving on clean, dry
pavement in Four-Wheel Drive
High for an extended period of
time may cause premature wear
on the vehicle's powertrain. Do
not drive on clean, dry pavement
in Four-Wheel Drive High for
extended periods of time.
While driving on clean dry pavement
and during tight turns, you may
experience a vibration in the
steering system.
Front Axle
The front axle engages and
disengages automatically when you
shift the transfer case. Some delay
for the axle to engage or disengage
is normal.
Automatic Transfer Case
The transfer case knob is located
to the left of the instrument panel
cluster.
Use this dial to shift into and out of
four-wheel drive.

Black plate (49,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-49
The vehicle has Four-Wheel Drive
with StabiliTrak®. For information on
StabiliTrak, see StabiliTrak®System
on page 9‑52.
You can choose among three
driving settings:
Indicator lights in the switch show
you which setting you are in. The
indicator lights will come on briefly
when you turn on the ignition and
the last chosen setting will stay on.
If the lights do not come on, you
should take the vehicle to your
dealer for service. An indicator light
will flash while shifting. It will stay on
when the shift is completed. If for
some reason the transfer case
cannot make a requested shift, it will
return to the last chosen setting.
2
m(Two-Wheel Drive High): This
setting is used for driving in most
street and highway situations.
The front axle is not engaged in
two-wheel drive. This setting also
provides the best fuel economy. AUTO (Automatic Four-Wheel
Drive):
This setting is ideal for
use when road surface traction
conditions are variable. When
driving the vehicle in AUTO, the
front axle is engaged, and the
vehicle's power is sent to the front
and rear wheels automatically
based on driving conditions. Driving
in this mode results in slightly lower
fuel economy than Two-Wheel
Drive High.
4
m(Four-Wheel Drive High): Use
the Four-Wheel Drive High position
when you need extra traction, such
as on snowy or icy roads or in most
off-road situations. This setting also
engages the front axle to help drive
the vehicle. This is the best setting
to use when plowing snow. Service Four‐Wheel Drive
If the SERVICE 4 WHEEL DRIVE
message stays on, you should
take the vehicle to your dealer
for service. See
“SERVICE
4 WHEEL DRIVE” message
under Transmission Messages on
page 5‑46.
Shifting Into Four-Wheel Drive
High or AUTO (Automatic
Four-Wheel Drive)
Turn the knob to the Four-Wheel
Drive High or AUTO position.
This can be done at any speed.
The indicator light will flash while
shifting. It will remain on when the
shift is completed.

Black plate (50,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-50 Driving and Operating
Shifting Into Two-Wheel
Drive High
Turn the knob to the Two-Wheel
Drive High position. This can be
done at any speed. The indicator
light will flash while shifting. It
will remain on when the shift is
completed.
Excessively shifting the transfer
case into or out of the different
modes may cause the transfer case
to enter the shift protection mode.
This will protect the transfer case
from possible damage and will only
allow the transfer case to respond
to one shift per 10 seconds. The
transfer case may stay in this mode
for up to three minutes.Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock
Brake System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the engine is started and the
vehicle begins to drive away, ABS
checks itself. A momentary motor or
clicking noise might be heard while
this test is going on, and it might
even be noticed that the brake
pedal moves a little. This is normal.If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
on page 5‑24.
If driving safely on a wet road and
it becomes necessary to slam on
the brakes and continue braking
to avoid a sudden obstacle, a
computer senses that the wheels
are slowing down. If one of the
wheels is about to stop rolling, the
computer will separately work the
brakes at each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
the driver steer around the obstacle
while braking hard.

Black plate (51,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-51
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You might hear the ABS
pump or motor operating and feel
the brake pedal pulsate, but this is
normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Parking Brake
Set the parking brake by holding the
regular brake pedal down, then
pushing down the parking brake
pedal.If the ignition is on, the brake
system warning light will come on.
See
Brake System Warning Light on
page 5‑23.
Notice: Driving with the parking
brake on can overheat the brake
system and cause premature
wear or damage to brake system
parts. Make sure that the parking
brake is fully released and the
brake warning light is off before
driving.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the parking brake pedal.
If the parking brake is not released
when you begin to drive, the brake
system warning light will flash and a
chime will sound warning you that
the parking brake is still on.
If you are towing a trailer and
are parking on a hill, see Driving
Characteristics and Towing Tips on
page 9‑75.

Black plate (52,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-52 Driving and Operating
Brake Assist
This vehicle has a brake assist
feature designed to assist the
driver in stopping or decreasing
vehicle speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement
the power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle. The
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsation or
pedal movement during this time
is normal and the driver should
continue to apply the brake pedal
as the driving situation dictates.
The brake assist feature will
automatically disengage when
the brake pedal is released or
brake pedal pressure is quickly
decreased.
Ride Control Systems
StabiliTrak®System
The vehicle has a vehicle stability
enhancement system called
StabiliTrak. It is an advanced
computer-controlled system that
assists the driver with directional
control of the vehicle in difficult
driving conditions.
StabiliTrak activates when the
computer senses a discrepancy
between the intended path and the
direction the vehicle is actually
traveling. StabiliTrak selectively
applies braking pressure at any one
of the vehicle's brakes to assist the
driver with keeping the vehicle on
the intended path.
When the vehicle is started and
begins to move, the system
performs several diagnostic checks
to insure there are no problems.
The system may be heard or felt
while it is working. This is normal
and does not mean there is a
problem with the vehicle.The system should initialize before
the vehicle reaches 32 km/h
(20 mph). In some cases, it may
take approximately 3.2 km (2 mi) of
driving before the system initializes.
If cruise control is being used
when StabiliTrak activates, the
cruise control automatically
disengages. The cruise control
can be re-engaged when road
conditions allow. See
Cruise Control
on page 9‑56.
If the system fails to turn on or
activate, the StabiliTrak light
along with one of the following
messages will be displayed on the
Driver Information Center (DIC):
TRACTION CONTROL OFF,
SERVICE TRACTION CONTROL,
STABILITRAK OFF, SERVICE
STABILITRAK. If these DIC
messages appear, make sure
the StabiliTrak system has not been
turned off using the StabiliTrak
on/off button. Then turn the vehicle
off, wait 15 seconds, and then turn it
back on again to reset the system.

Black plate (53,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-53
If any of these messages still
appear on the Driver Information
Center (DIC), the vehicle should
be taken in for service. For more
information on the DIC messages,
seeDriver Information Center (DIC)
on page 5‑28.
The StabiliTrak light will flash on the
instrument panel cluster when the
system is both on and activated.
The system may be heard or felt
while it is working; this is normal.
The traction control disable button is
located on the instrument panel.
The traction control part of
StabiliTrak can be turned off
by pressing and releasing the
StabiliTrak button if both systems
(traction control and StabiliTrak)
were previously on. To disable both
TCS and StabiliTrak, press and
hold
5untilFilluminates and the
appropriate DIC message displays.
Traction control and StabiliTrak
can be turned on by pressing and
releasing the StabiliTrak button if
they are not automatically shut off
for any other reason. When the traction control system
(TCS) or StabiliTrak system is
turned off, the StabiliTrak light
and the appropriate TCS off or
StabiliTrak off message will be
displayed on the DIC to warn the
driver. The vehicle will still have
brake-traction control when traction
control is off, but will not be able to
use the engine speed management
system. See
“Traction Control
Operation” next for more
information.
When the traction control system
has been turned off, system noises
may still be heard as a result of the
brake-traction control coming on.

Black plate (54,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-54 Driving and Operating
It is recommended to leave the
system on for normal driving
conditions, but it may be necessary
to turn the system off if the vehicle
is stuck in sand, mud, ice or snow,
and you want to“rock”the vehicle
to attempt to free it. It may also be
necessary to turn off the system
when driving in extreme off-road
conditions where high wheel spin is
required. See If the Vehicle is Stuck
on page 9‑22.
When the transfer case is in 4LO,
the stability system is automatically
disabled, the StabiliTrak light comes
on, and the STABILITRAK OFF
message will appear on the DIC.
Both traction control and StabiliTrak
are automatically disabled in this
condition.
Traction Control Operation
The traction control system is
part of the StabiliTrak system.
Traction control limits wheel spin
by reducing engine power to the
wheels (engine speed management) and by applying brakes to each
individual wheel (brake-traction
control) as necessary.
The traction control system is
enabled automatically when the
vehicle is started. It will activate and
the StabiliTrak light will flash if it
senses that any of the wheels are
spinning or beginning to lose
traction while driving. If traction
control is turned off, only the
brake-traction control portion of
traction control will work. The
engine speed management will
be disabled. In this mode, engine
power is not reduced automatically
and the driven wheels can spin
more freely. This can cause the
brake-traction control to activate
constantly.
Notice:
If the wheel(s) of one axle
is allowed to spin excessively
while the StabiliTrak®, ABS, brake
warning lights, and any relevant
DIC messages are displayed, the
transfer case could be damaged.
The repairs would not be covered
by the vehicle warranty. Reduce engine power and do not spin
the wheel(s) excessively while
these lights and messages are
displayed.
The traction control system may
activate on dry or rough roads or
under conditions such as heavy
acceleration while turning or
abrupt upshifts/downshifts of the
transmission. When this happens,
a reduction in acceleration may be
noticed, or a noise or vibration may
be heard. This is normal.
If cruise control is being used when
the system activates, the StabiliTrak
light will flash and cruise control will
automatically disengage. Cruise
control may be reengaged when
road conditions allow. See
Cruise
Control on page 9‑56.
StabiliTrak may also turn off
automatically if it determines that
a problem exists with the system.
If the problem does not clear itself
after restarting the vehicle, see your
dealer for service.

Black plate (55,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-55
Locking Rear Axle
Vehicles with a locking rear axle can
give more traction on snow, mud,
ice, sand, or gravel. It works like a
standard axle most of the time, but
when traction is low, this feature will
allow the rear wheel with the most
traction to move the vehicle.
Continuous Damping
Control (CDC)
This vehicle may have a continuous
damping control system called
Autoride
®or MagneRide™. With
this feature, improved vehicle ride
and handling is provided under a
variety of passenger and loading
conditions.
Autoride and MagneRide are fully
automatic and use a computer
controller to continuously monitor
vehicle speed, wheel to body
position, lift/dive and steering
position of the vehicle. The
controller then sends signals
to each shock absorber to independently adjust the damping
level to provide the optimum
vehicle ride.
Autoride and MagneRide also
interact with the tow/haul mode
that, when activated, will provide
additional control of the shock
absorbers. This additional control
results in better ride and handling
characteristics when the vehicle is
loaded or towing a trailer. See
“Tow/Haul Mode”
underTrailer
Towing on page 9‑79 for more
information.Automatic Level Control
The automatic level control rear
suspension is available on
light‐duty vehicles and comes as a
part of the Continuous Damping
Control (CDC) suspension,
if equipped. This type of level control is fully
automatic and will provide a better
leveled riding position as well as
better handling under a variety of
passenger and loading conditions.
An air compressor connected to
the rear shocks will raise or lower
the rear of the vehicle to maintain
proper vehicle height. The system
is activated when the ignition key
is turned to ON/RUN and will
automatically adjust vehicle height
thereafter. The system may exhaust
(lower vehicle height) for up to
ten minutes after the ignition key
has been turned off. You may hear
the air compressor operating when
the height is being adjusted.
If a weight‐distributing hitch is
being used, it is recommended to
allow the shocks to inflate, thereby
leveling the vehicle prior to adjusting
the hitch.