wheel GMC YUKON 2015 Repair Manual

Black plate (41,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-41
The settings are:
2
m(Two-Wheel Drive High):Use
for driving on most streets and
highways. The front axle is not
engaged. This setting provides the
best fuel economy.
AUTO (Automatic Four-Wheel
Drive): Use when road surface
traction conditions are variable.
When driving 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. This setting
provides slightly lower fuel economy
than 2
m.
Do not use AUTO mode to park on
a steep grade with poor traction
such as ice, snow, mud, or gravel.
In AUTO mode only the rear wheels
will hold the vehicle from sliding
when parked. If parking on a steep
grade, use 4
mto keep all four
wheels engaged. 4
m(Four-Wheel Drive High):
Use
this position when extra traction is
needed, such as when driving on
snowy or icy roads, when
off-roading, or when plowing snow.
Service Four-Wheel Drive
If the SERVICE 4WD message
stays on, you should take the
vehicle to your dealer for service.
See “SERVICE 4WD” message
under Transmission Messages on
page 5-40.
Shifting Into 4
mor AUTO
Turn the knob to the 4
mor 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.
Shifting Into 2
m
Turn the knob to the 2mposition.
This can be done at any speed.
The indicator light will flash while
shifting. It will remain on when the
shift is completed.
Brakes
Antilock Brake
System (ABS)
This vehicle has ABS, an advanced
electronic braking system that helps
prevent a braking skid.
When 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. See Antilock
Brake System (ABS) Warning Light
on page 5-22.

Black plate (42,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
9-42 Driving and Operating
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 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
you steer around the obstacle while
braking hard.
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 vehiclesuddenly 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 may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
Braking in Emergencies
ABS allows you 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 5-21.

Black plate (44,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
9-44 Driving and Operating
not activate if the vehicle is in a
drive gear and facing downhill or if
the vehicle is facing uphill and in
R (Reverse). There may be
situations on minor hills (less than
5% grade) with a loaded vehicle or
while pulling a trailer where HSA will
not activate.Ride Control Systems
Traction Control/
Electronic Stability
Control
System Operation
The vehicle has a Traction Control
System (TCS) and StabiliTrak®, an
electronic stability control system.
These systems help limit wheel spin
and assist the driver in maintaining
control, especially on slippery road
conditions.
TCS activates if it senses that any
of the drive wheels are spinning or
beginning to lose traction. When this
happens, TCS applies the brakes to
the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak activates when the
vehicle senses a difference between
the intended path and the direction
the vehicle is actually traveling.
StabiliTrak selectively applies
braking pressure to any one of the vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path. Trailer Sway Control
(TSC) is also on automatically when
the vehicle is started. See
Trailer
Sway Control (TSC) on page 9-88.
If cruise control is being used and
traction control or StabiliTrak begins
to limit wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.

Black plate (45,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-45
SeeIf the Vehicle Is Stuck on
page 9-13 and“Turning the
Systems Off and On” later in this
section.
When the transfer case is in
Four-Wheel Drive Low, the stability
system is automatically disabled,
the StabiliTrak OFF light comes on,
and the appropriate message will
appear on the DIC. Both traction
control and StabiliTrak are
automatically disabled in this
condition.
The indicator light for both systems
is in the instrument cluster. This
light will:
.Flash when TCS is limiting
wheel spin.
.Flash when StabiliTrak is
activated.
.Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.
If
dcomes on and stays on:
1. Stop the vehicle.
2. Turn the engine off and wait 15 seconds.
3. Start the engine.
Drive the vehicle. If
dcomes on
and stays on, the vehicle may need
more time to diagnose the problem.
If the condition persists, see your
dealer.
Turning the Systems Off
and On
The button for TCS and StabiliTrak
is on the instrument panel to the left
of the steering wheel.
{Caution
Do not repeatedly brake or
accelerate heavily when TCS is
off. The vehicle driveline could be
damaged.
To turn off only TCS, press and
release the
gbutton. The traction
off light
idisplays in the instrument
cluster. The appropriate message
will display in the DIC. See Ride
Control System Messages on
page 5-37.

Black plate (46,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
9-46 Driving and Operating
To turn TCS on again, press and
release the
gbutton. The traction
off light
idisplayed in the
instrument cluster will turn off.
If TCS is limiting wheel spin when
the
gbutton is pressed, the system
will not turn off until the wheels stop
spinning.
To turn off both TCS and StabiliTrak,
press and hold the
gbutton until
the traction off light
iand the
StabiliTrak OFF light
gcome on
and stay on in the instrument
cluster, then release. The
appropriate message will display in
the DIC. See Ride Control System
Messages on page 5-37.
To turn TCS and StabiliTrak on
again, press and release the
g
button. The traction off lightiand
the StabiliTrak OFF light
gin the
instrument cluster turn off. StabiliTrak will automatically turn on
if the vehicle exceeds 56 km/h
(35 mph). Traction control will
remain off.
The vehicle has a Trailer Sway
Control (TSC) feature and a Hill
Start Assist (HSA) feature. See
Trailer Sway Control (TSC) on
page 9-88
orHill Start Assist (HSA)
on page 9-43.
Adding accessories can affect the
vehicle performance. See
Accessories and Modifications on
page 10-3.
Hill Descent
Control (HDC)
If equipped, HDC can be used when
driving downhill. It sets and
maintains vehicle speed while
descending a very steep incline in a
forward or reverse gear.
The HDC switch is on the
instrument panel to the left of the
steering wheel. Press
5to enable or disable HDC.
Vehicle speed must be below
50 km/h (31 mph).
The HDC light displays on the
instrument cluster when enabled.
HDC can maintain vehicle speeds
between 3 and 22 km/h (2 and
14 mph) on an incline greater than
or equal to a 10% grade. A blinking
HDC light indicates that the system
is actively applying the brakes to
maintain vehicle speed.
When HDC is set, that is the initial
set speed. It can be increased or
decreased by applying the
accelerator or brake pedal. This
adjusted speed becomes the new
set speed.

Black plate (47,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-47
HDC will remain enabled between
22 and 60 km/h (14 and 37 mph),
however vehicle speed cannot be
set or maintained in this range.
It will automatically disable if the
vehicle speed is above 80 km/h
(50 mph) or above 60 km/h
(37 mph) for at least 30 seconds.
5
must be pressed again to
re-enable HDC.
When enabled, if the vehicle is at a
speed above 22 km/h (14 mph) and
less than 60 km/h (37 mph), a DIC
message will display.
Magnetic Ride Control
This vehicle may have a semi-active
damping system called
MagneRide
®. With this feature,
improved vehicle ride and handling
is provided under a variety of
passenger and loading conditions. MagneRide is fully automatic and
uses 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.
MagneRide also interacts 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”
under Trailer Towing on page 9-78.
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.
Automatic Level Control
The automatic level control rear
suspension is available on light-duty
vehicles and comes as a part of the
MagneRide suspension, if equipped.
Automatic Level Control (ALC) may
also be available as a stand alone
feature.
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

Black plate (48,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
9-48 Driving and Operating
turned to ON/RUN and will
automatically adjust vehicle height
thereafter. The system may exhaust
(lower vehicle height) for up to
10 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.Cruise Control
{Warning
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. 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).
If the brakes are applied, the cruise
control disengages. This vehicle has a Hydra-Matic
6-speed automatic transmission.
See
“Grade Braking” underTow/
Haul Mode on page 9-35 for an
explanation of how cruise control
interacts with the Range Selection
Mode, Tow/Haul Mode and Grade
Braking systems.
This vehicle has StabiliTrak and
when the system begins to limit
wheel spin, the cruise control will
automatically disengage. See
Traction Control/Electronic Stability
Control on page 9-44. If a collision
alert occurs when cruise control is
activated, cruise control is
disengaged. See Forward Collision
Alert (FCA) System on page 9-62.
When road conditions allow the
cruise control to be safely used
again, it can be turned back on.

Black plate (49,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-49
5(On/Off):Press to turn the
system on or off. A white indicator
comes on in the instrument cluster.
SET −(Set/Coast): Press briefly to
set the speed and activate cruise
control. If cruise control is already
active, use to decrease vehicle
speed.
+RES (Resume/Accelerate): If
there is a set speed in memory
press to resume that speed or press
and hold to accelerate. If cruise
control is already active, use to
increase vehicle speed.
*(Cancel): Press to disengage
cruise control without erasing the
set speed from memory.
Setting Cruise Control
If
5is on when not in use, the
SET− or SET− control could get
pressed and go into cruise when not
desired. Keep the cruise
5button
off when cruise is not being used.
The cruise control light on the
instrument cluster will come on
green after the cruise control has
been set to the desired speed.
1. Press
5to turn the cruise
system on.
2. Get up to the desired speed.
3. Press and release the SET− button on the steering wheel.
The desired set speed briefly
appears in the instrument panel
cluster.
4. Remove foot from the accelerator. The cruise control indicator on the
instrument cluster turns green after
cruise control has been set to the
desired speed. See
Instrument
Cluster on page 5-10.
Resuming a Set Speed
If the cruise control is set at a
desired speed and then the brakes
are applied, the cruise control is
disengaged without erasing the set
speed from memory.
Once the vehicle speed reaches
about 40 km/h (25 mph) or more,
briefly press the +RES button on the
steering wheel. The vehicle returns
to the previous set speed.
Increasing Speed While Using
Cruise Control
If the cruise control system is
already activated:
.Press and hold the +RES button
on the steering wheel until the
vehicle accelerates to the
desired speed, then release it.

Black plate (52,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
9-52 Driving and Operating
{Warning
Adaptive Cruise Control will not
detect or brake for children,
pedestrians, animals, or other
objects.
Do not use Adaptive Cruise
Control when:
.On winding and hilly roads or
when the sensors are
blocked by snow, ice, or dirt.
The system may not detect a
vehicle ahead. Keep the
entire front of the vehicle
clean.
.Visibility is low, such as in
fog, rain, or snow conditions.
Adaptive Cruise Control
performance is limited under
these conditions.
.On slippery roads where fast
changes in tire traction can
cause excessive wheel slip.
5(On/Off):Press to turn the
system on or off. The indicator turns
white on the instrument cluster
when ACC is turned on.
SET– (Set/Coast): Press briefly to
set the speed and activate ACC.
If cruise control is already active,
use to decrease vehicle speed.
+RES (Resume/Accelerate):
Press briefly to resume the previous
set speed or hold to accelerate.
If ACC is already active, use to
increase vehicle speed.
*(Cancel): Press to disengage
ACC without erasing the selected
set speed.
3(Follow Distance Gap): Press
to select a following gap time (or
distance) setting for ACC of Far,
Medium, or Near.
Setting Adaptive Cruise Control
If the cruise button is on when not in
use, the cruise on/off control could
get pressed and cruise control could
become active when not desired.
Keep the cruise control off when
cruise is not being used.
Select the set speed desired for
cruise. This is the vehicle speed
when no vehicle is detected in
its path.
ACC will not set or resume at a
speed less than 25 km/h (16 mph).
To set ACC:
1. Press
5.
2. Get up to the desired speed.

Black plate (53,1)GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-7063682) - 2015 - CRC - 6/5/14
Driving and Operating 9-53
3. Press and release the SET–control on the steering wheel.
4. Remove foot from the accelerator.
After ACC is set, it may immediately
apply the brakes if a vehicle ahead
is detected closer than the selected
following gap.
The ACC indicator displays on the
Driver Information Center (DIC) in
the instrument cluster. When ACC is
active, the indicator turns green.
Be mindful of speed limits,
surrounding traffic speeds, and
weather conditions when selecting
the set speed. Resuming a Set Speed
If the ACC is set at a desired speed
and then the brakes are applied,
ACC is disengaged without erasing
the set speed from memory.
To begin using ACC again, press
+RES on the steering wheel. The
vehicle returns to the previous set
speed.
Increasing Speed While ACC is at
a Set Speed
If ACC is already activated, do one
of the following:
.Use the accelerator to get to the
higher speed. Press SET–
.
Release the button and the
accelerator pedal. The vehicle
will now cruise at the higher
speed.
When the accelerator pedal is
pressed, ACC will not brake
because it is overridden.
A warning message will appear
on the Driver Information Center
(DIC). See Cruise Control
Messages on page 5-32.
.Press and hold +RES until the
desired set speed appears on
the display, then release it.
.To increase vehicle speed in
small increments, briefly press
+RES. For each press, the
vehicle goes to the next 5 km/h
(1 mph) faster mark on the
speedometer.
When it is determined that there is
no vehicle ahead or the vehicle
ahead is beyond the selected
following gap, then the vehicle
speed will increase to the set speed.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster on
page 5-10. The increment value
used depends on the units
displayed.