MAINT GMC YUKON 2011 Owner's Guide

Black plate (8,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-8 Driving and Operating
Before You Go Off-Roading
.Have all necessary maintenance
and service work done.
.Make sure there is enough fuel,
that fluid levels are where they
should be, and that the spare
tire, if the vehicle has one, is
fully inflated.
.Be sure to read all the
information about
four-wheel-drive vehicles
in this manual.
.Make sure all underbody
shields, if the vehicle has them,
are properly attached.
.Know the local laws that apply
to off-roading where you will
be driving or check with law
enforcement people in the area.
.Be sure to get the necessary
permission if you will be on
private land.If you think you will need some
more ground clearance at the front
of your vehicle, you can remove the
front fascia lower air dam. The air
dam is held in place by two bolts
and 10 snaps accessible from
underneath the front fascia.
To remove the air dam:
1. Remove the two outboard air
dam bolts.
2. With a flat‐blade tool, disengage the snaps.
3. After the bolts are removed and the snaps are disengaged, push
forward on the air dam until it
is free.
Notice: Operating your vehicle
for extended periods without
the front fascia lower air dam
installed can cause improper air
flow to the engine. Always be
sure to replace the front fascia
air dam when you are finished
off-road driving. After off-roading, be sure to reinstall
the air dam:
1. Line up the snaps and push the
air dam rearward to engage the
snaps.
2. Install the two outboard bolts.
Loading Your Vehicle for
Off-Road Driving
{WARNING
.Cargo on the load floor piled
higher than the seatbacks
can be thrown forward during
a sudden stop. You or your
passengers could be injured.
Keep cargo below the top of
the seatbacks.
.Unsecured cargo on the
load floor can be tossed
about when driving over
rough terrain. You or your
passengers can be struck
by flying objects. Secure the
cargo properly. (Continued)

Black plate (12,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-12 Driving and Operating
Approaching a Hill
When you approach a hill, decide if
it is too steep to climb, descend,
or cross. Steepness can be hard
to judge. On a very small hill, for
example, there may be a smooth,
constant incline with only a small
change in elevation where you can
easily see all the way to the top.
On a large hill, the incline may get
steeper as you near the top, but you
might not see this because the crest
of the hill is hidden by bushes,
grass, or shrubs.
Consider this as you approach a hill:
.Is there a constant incline,
or does the hill get sharply
steeper in places?
.Is there good traction on the
hillside, or will the surface cause
tire slipping?
.Is there a straight path up
or down the hill so you will
not have to make turning
maneuvers?
.Are there obstructions on the hill
that can block your path, such
as boulders, trees, logs, or ruts?
.What is beyond the hill? Is
there a cliff, an embankment, a
drop-off, a fence? Get out and
walk the hill if you do not know.
It is the smart way to find out.
.Is the hill simply too rough?
Steep hills often have ruts,
gullies, troughs, and exposed
rocks because they are more
susceptible to the effects of
erosion.
Driving Uphill
Once you decide it is safe to drive
up the hill:
.Use a low gear and get a firm
grip on the steering wheel.
.Get a smooth start up the hill
and try to maintain speed. Not
using more power than needed
can avoid spinning the wheels or
sliding.
{WARNING
Turning or driving across steep
hills can be dangerous. You could
lose traction, slide sideways, and
possibly roll over. You could be
seriously injured or killed. When
driving up hills, always try to go
straight up.
.Try to drive straight up the hill if
at all possible. If the path twists
and turns, you might want to find
another route.
.Ease up on the speed as you
approach the top of the hill.
.Attach a flag to the vehicle to be
more visible to approaching
traffic on trails or hills.
.Sound the horn as you approach
the top of the hill to let opposing
traffic know you are there.

Black plate (14,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-14 Driving and Operating
Exit on the uphill side and stay clear
of the path the vehicle would take if
it rolled downhill. If the vehicle has
a transfer case with a N (Neutral)
position, do not shift the transfer
case to Neutral when you leave the
vehicle. Leave it in some gear.
{WARNING
If the vehicle has the two‐speed
automatic transfer case, shifting
the transfer case to Neutral can
cause your vehicle to roll even if
the transmission is in P (Park).
This is because the Neutral
position on the transfer case
overrides the transmission. You
or someone else could be injured.
If you are going to leave your
vehicle, set the parking brake
and shift the transmission to
P (Park). But, if the vehicle has
a two‐speed automatic transfer
case, do not shift the transfer
case to Neutral.
Driving Downhill
When off-roading takes you
downhill, consider:
.How steep is the downhill? Will
I be able to maintain vehicle
control?
.What is the surface like?
Smooth? Rough? Slippery?
Hard-packed dirt? Gravel?
.Are there hidden surface
obstacles? Ruts? Logs?
Boulders?
.What is at the bottom of the hill?
Is there a hidden creek bank or
even a river bottom with large
rocks?
If you decide you can go down a
hill safely, try to keep the vehicle
headed straight down. Use a low
gear so engine drag can help the
brakes so they do not have to do all
the work. Descend slowly, keeping
the vehicle under control at all
times.
{WARNING
Heavy braking when going down
a hill can cause your brakes to
overheat and fade. This could
cause loss of control and a
serious accident. Apply the
brakes lightly when descending a
hill and use a low gear to keep
vehicle speed under control.
Things not to do when driving down
a hill:
.When driving downhill, avoid
turns that take you across the
incline of the hill. A hill that is not
too steep to drive down might be
too steep to drive across. The
vehicle could roll over.
.Never go downhill with the
transmission in N (Neutral),
called free-wheeling. The brakes
will have to do all the work and
could overheat and fade.

Black plate (17,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-17
Driving in Water
{WARNING
Driving through rushing water can
be dangerous. Deep water can
sweep your vehicle downstream
and you and your passengers
could drown. If it is only shallow
water, it can still wash away the
ground from under your tires, and
you could lose traction and roll
the vehicle over. Do not drive
through rushing water.
Heavy rain can mean flash flooding,
and flood waters demand extreme
caution. Find out how deep the water is
before driving through it. Do not try
it if it is deep enough to cover the
wheel hubs, axles, or exhaust
pipe
—you probably will not get
through. Deep water can damage
the axle and other vehicle parts.
If the water is not too deep, drive
slowly through it. At faster speeds,
water splashes on the ignition
system and the vehicle can stall.
Stalling can also occur if you get the
tailpipe under water. If the tailpipe is
under water, you will never be able
to start the engine. When going
through water, remember that when
the brakes get wet, it might take
longer to stop. See Driving on Wet
Roads on page 9‑18.
After Off-Road Driving
Remove any brush or debris that
has collected on the underbody,
chassis, or under the hood. These
accumulations can be a fire hazard.
After operation in mud or sand,
have the brake linings cleaned and
checked. These substances can
cause glazing and uneven braking.
Check the body structure, steering,
suspension, wheels, tires, and
exhaust system for damage and
check the fuel lines and cooling
system for any leakage.
The vehicle requires more frequent
service due to off-road use. Refer
to the Maintenance Schedule for
additional information.

Black plate (35,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-35
The shift lock release is always
functional except in the case of an
uncharged or low voltage (less than
9 volt) battery.
If the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. SeeJump Starting on
page 10‑88 for more information.
To shift out of P (Park) use the
following:
1. Apply the brake pedal.
2. Move the shift lever to the desired position.
If you still are unable to shift out of
P (Park):
1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, press the shift lever all
the way into P (Park).
3. Move the shift lever to the desired position. If you are still having a problem
shifting, then have the vehicle
serviced soon.
Parking Over Things
That Burn
{WARNING
Things that can burn could touch
hot exhaust parts under the
vehicle and ignite. Do not park
over papers, leaves, dry grass,
or other things that can burn.
Active Fuel Management®
Vehicles with V8 engines may have
Active Fuel Management™. This
system allows the engine to operate
on either all or half of its cylinders,
depending on the driving conditions.
When less power is required, such
as cruising at a constant vehicle
speed, the system will operate in
the half cylinder mode, allowing
the vehicle to achieve better fuel
economy. When greater power
demands are required, such as
accelerating from a stop, passing,
or merging onto a freeway, the
system will maintain full-cylinder
operation.
If the vehicle has an Active Fuel
Management™
indicator, seeDriver
Information Center (DIC) on
page 5‑28 for more information on
using this display.

Black plate (39,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-39
{WARNING
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed.
Notice: Shifting out of P (Park)
or N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle. D (Drive):
This position is for
normal driving. It provides the best
fuel economy. If you need more
power for passing, and you are:
.Going less than about 55 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 55 km/h (35 mph) or
more, push the accelerator all
the way down.
By doing this, the vehicle shifts
down to the next gear and has
more power.
D (Drive) can be used when towing
a trailer, carrying a heavy load,
driving on steep hills, or for off-road
driving. You might want to shift
the transmission to a lower gear
selection if the transmission shifts
too often.
Downshifting the transmission in
slippery road conditions could result
in skidding. See “Skidding”under
Loss of Control on page 9‑6. The vehicle has a shift stabilization
feature that adjusts the transmission
shifting to the current driving
conditions in order to reduce rapid
upshifts and downshifts. This shift
stabilization feature is designed
to determine, before making an
upshift, if the engine is able to
maintain vehicle speed by analyzing
things such as vehicle speed,
throttle position, and vehicle load.
If the shift stabilization feature
determines that a current vehicle
speed cannot be maintained, the
transmission does not upshift and
instead holds the current gear. In
some cases, this could appear
to be a delayed shift, however the
transmission is operating normally.
The vehicle's transmission
uses adaptive shift controls.
Adaptive shift controls continually
compares key shift parameters to
pre-programmed ideal shifts stored
in the transmissions computer.

Black plate (42,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-42 Driving and Operating
Tow/Haul Mode
The vehicle has a Tow/Haul Mode.
The selector button is located on the
end of the column shift lever. You
can use this feature to assist when
towing or hauling a heavy load or if
there is a need to charge a battery
installed in a trailer. SeeTowing
Equipment on page 9‑84 for more
information.
When Tow/Haul Mode is selected
the tow/haul indicator light will
come on. The Tow/Haul Mode works with the
Autoride
®feature, if the vehicle
has this, to enhance the ride when
trailering or with a loaded vehicle.
See Continuous Damping Control
(CDC) on page 9‑55.
Grade Braking (Hydra-Matic®
6-Speed Automatic
Transmission)
The Grade Braking shift modes can
be activated by pressing the button
on the end of the shift control lever.
While in Range Selection Mode,
Grade Braking is deactivated
allowing the driver to select a
desired range of gears.
Grade Braking is only active while
the Tow/Haul Mode is selected and
you are not in the Range Selection
Mode. See “Tow/Haul Mode” listed
previously and Manual Mode on
page 9‑41 for more information on
the Range Selection Mode. Grade
Braking assists in maintaining
desired vehicle speeds when driving on downhill grades by automatically
implementing a shift schedule that
utilizes the engine and transmission
to slow the vehicle. This reduces
wear on the braking system and
increases control of the vehicle.
Grade Braking monitors vehicle
speed, acceleration, engine torque
and brake pedal usage. Using this
information, it detects when the
truck is on a downhill grade and the
driver desires to slow the vehicle by
pressing the brake.
Also see
Towing Equipment on
page 9‑84 for more information.
Cruise Grade Braking
(Hydra-Matic®6-Speed
Automatic Transmission)
Cruise Grade Braking assists
when driving on a downhill grade.
It maintains vehicle speed by
automatically implementing a shift
schedule that uses the engine and
the transmission to slow the vehicle.

Black plate (43,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-43
Cruise Grade Braking operates
while Cruise Control is engaged
in Tow/Haul Mode to assist in
maintaining vehicle speed under
loaded vehicle conditions. It utilizes
vehicle acceleration and deviation
from desired speed to determine
the correct gear for the operating
condition. If vehicle speed is above
the desired speed the transmission
will downshift to slow the vehicle.
If vehicle speed is near or below
desired speed the trans will upshift,
allowing vehicle speed to increase.
While in the Range Selection
Mode, Cruise Grade Braking is not
available.
See“Range Selection Mode” under
Manual Mode on page 9‑41.Drive Systems
Four-Wheel Drive (Two
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 or Four-Wheel Drive Low 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 or
Four-Wheel Drive Low for
extended periods of time. While driving on clean dry pavement
and during tight turns, you may
experience a vibration in the
steering system.
The vehicle has StabiliTrak
®.
Shifting into Four-Wheel Drive
Low will turn Traction Control and
StabiliTrak off. See StabiliTrak
®
System on page 9‑52.
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.

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.

Black plate (56,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-56 Driving and Operating
Cruise Control
{WARNING
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. So, do not use
the cruise control on winding
roads or in heavy traffic.
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads.
With cruise control, a speed of
about 40 km/h (25 mph) or more can
be maintained without keeping your
foot on the accelerator. Cruise
control does not work at speeds
below about 40 km/h (25 mph).
When the brakes are applied, cruise
control is turned off. If the vehicle has StabiliTrak and the
system begins to limit wheel spin,
cruise control will automatically
disengage. See
StabiliTrak
®System
on page 9‑52. When road conditions
allow the cruise control to be safely
used again, it can be turned
back on.
The cruise control buttons are
located on left side of the steering
wheel.
I(On/Off): Press to turn the
system on or off. The indicator light
is on when cruise control is on and
turns off when cruise control is off. +RES (Resume/Accelerate):
Press briefly to make the vehicle
resume to a previously set speed,
or press and hold to accelerate.
SET−
(Set/Coast): Press to set the
speed and activate cruise control or
make the vehicle decelerate.
[(Cancel): Press to disengage
cruise control without erasing the
set speed from memory.
Setting Cruise Control
If the cruise button is on when not in
use, it could get bumped and go into
cruise when not desired. Keep the
cruise control switch off when cruise
is not being used.
The cruise control light on the
instrument panel cluster comes on
after the cruise control has been set
to the desired speed.
1. Press the
Ibutton.
2. Get up to the desired speed.