engine GMC YUKON 2011 Repair Manual

Black plate (19,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-19
Highway Hypnosis
Always be alert and pay attention
to your surroundings while driving.
If you become tired or sleepy, find
a safe place to park the vehicle
and rest.
Other driving tips include:
.Keep the vehicle well ventilated.
.Keep interior temperature cool.
.Keep your eyes moving—scan
the road ahead and to the sides.
.Check the rearview mirror and
vehicle instruments often.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips for
driving in these conditions include:
.Keep the vehicle serviced and in
good shape.
.Check all fluid levels and brakes,
tires, cooling system, and
transmission.
.Shift to a lower gear when going
down steep or long hills.
{WARNING
If you do not shift down, the
brakes could get so hot that they
would not work well. You would
then have poor braking or even
none going down a hill. You could
crash. Shift down to let the engine
assist the brakes on a steep
downhill slope.
{WARNING
Coasting downhill in N (Neutral)
or with the ignition off is
dangerous. The brakes will have
to do all the work of slowing down
and they could get so hot that
they would not work well. You
would then have poor braking or
even none going down a hill.
(Continued)
WARNING (Continued)
You could crash. Always have the
engine running and the vehicle in
gear when going downhill.
.Stay in your own lane. Do not
swing wide or cut across the
center of the road. Drive at
speeds that let you stay in your
own lane.
.Top of hills: Be
alert—something could
be in your lane (stalled car,
accident).
.Pay attention to special road
signs (falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.

Black plate (20,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-20 Driving and Operating
Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow
or ice between the tires and the
road, creating less traction or grip.
Wet ice can occur at about 0°C
(32°F) when freezing rain begins to
fall, resulting in even less traction.
Avoid driving on wet ice or in
freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the
condition. Accelerate gently so
traction is not lost. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick, so there is even less
traction.
Try not to break the fragile traction.
If you accelerate too fast, the drive
wheels will spin and polish the
surface under the tires even more.The
Antilock Brake System (ABS)
on page 9‑50 improves vehicle
stability during hard stops on
slippery roads, but apply the
brakes sooner than when on dry
pavement.
Allow greater following distance on
any slippery road and watch for
slippery spots. Icy patches can
occur on otherwise clear roads in
shaded areas. The surface of a
curve or an overpass can remain
icy when the surrounding roads
are clear. Avoid sudden steering
maneuvers and braking while
on ice.
Turn off cruise control on slippery
surfaces.
Blizzard Conditions
Being stuck in snow can be a
serious situation. Stay with the
vehicle unless there is help nearby.
If possible, use the Roadside
Assistance Program on page 13‑6.
To get help and keep everyone in
the vehicle safe:
.Turn on the hazard warning
flashers.
.Tie a red cloth to an outside
mirror.
{WARNING
Snow can trap engine exhaust
under the vehicle. This may
cause exhaust gases to get
inside. Engine exhaust contains
Carbon Monoxide (CO) which
cannot be seen or smelled. It can
cause unconsciousness and even
death.
(Continued)

Black plate (21,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-21
WARNING (Continued)
If the vehicle is stuck in the snow:
.Clear away snow from around
the base of your vehicle,
especially any that is blocking
the exhaust pipe.
.Check again from time to
time to be sure snow does
not collect there.
.Open a window about 5 cm
(2 in) on the side of the
vehicle that is away from the
wind to bring in fresh air.
.Fully open the air outlets on
or under the instrument
panel.(Continued)
WARNING (Continued)
.Adjust the climate control
system to a setting that
circulates the air inside the
vehicle 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.
Snow can trap exhaust gases
under your vehicle. This can
cause deadly CO (Carbon
Monoxide) gas to get inside. CO
could overcome you and kill you.
You cannot see it or smell it, so
you might not know it is in your
vehicle. Clear away snow from
around the base of your vehicle,
especially any that is blocking the
exhaust. Run the engine for short periods
only as needed to keep warm, but
be careful.
To save fuel, run the engine for only
short periods as needed to warm
the vehicle and then shut the engine
off and close the window most of
the way to save heat. Repeat this
until help arrives but only when you
feel really uncomfortable from the
cold. Moving about to keep warm
also helps.
If it takes some time for help to
arrive, now and then when you run
the engine, push the accelerator
pedal slightly so the engine runs
faster than the idle speed. This
keeps the battery charged to restart
the vehicle and to signal for help
with the headlamps. Do this as little
as possible to save fuel.

Black plate (22,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-22 Driving and Operating
If the Vehicle is Stuck
Slowly and cautiously spin the
wheels to free the vehicle when
stuck in sand, mud, ice, or snow.
If the vehicle has a traction system,
it can often help to free a stuck
vehicle. Refer to the vehicle's
traction system in the Index. If stuck
too severely for the traction system
to free the vehicle, turn the traction
system off and use the rocking
method.
{WARNING
If the vehicle's tires spin at high
speed, they can explode, and you
or others could be injured. The
vehicle can overheat, causing an
engine compartment fire or other
damage. Spin the wheels as little
as possible and avoid going
above 55 km/h (35 mph).For information about using tire
chains on the vehicle, see
Tire
Chains on page 10‑70.
Rocking the Vehicle to Get
it Out
Turn the steering wheel left and
right to clear the area around the
front wheels. For four-wheel-drive
vehicles, shift into Four‐Wheel High
or, if the vehicle has a two‐speed
automatic transfer case, Four‐Wheel
Low. For vehicles with StabiliTrak
®,
turn the traction control part of the
system off. Shift back and forth
between R (Reverse) and a forward
gear, spinning the wheels as little as
possible. To prevent transmission
wear, wait until the wheels stop
spinning before shifting gears.
Release the accelerator pedal
while shifting, and press lightly on
the accelerator pedal when the
transmission is in gear. Slowly
spinning the wheels in the forward and reverse directions causes a
rocking motion that could free the
vehicle. If that does not get the
vehicle out after a few tries, it might
need to be towed out. Recovery
hooks can be used, if the vehicle
has them. If the vehicle does need
to be towed out, see
Towing the
Vehicle on page 10‑93.
Recovery Hooks
{WARNING
These hooks, when used, are
under a lot of force. Always pull
the vehicle straight out. Never
pull on the hooks at a sideways
angle. The hooks could break
off and you or others could be
injured from the chain or cable
snapping back.

Black plate (28,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-28 Driving and Operating
Starting and
Operating
New Vehicle Break-In
Notice:The vehicle does not
need an elaborate break-in. But it
will perform better in the long run
if you follow these guidelines:
.Keep the vehicle speed at
88 km/h (55 mph) or less for
the first 805 km (500 miles).
.Do not drive at any one
constant speed, fast or
slow, for the first 805 km
(500 miles). Do not make
full-throttle starts. Avoid
downshifting to brake or
slow the vehicle.
.Avoid making hard stops for
the first 322 km (200 miles) or
so. During this time the new
brake linings are not yet
broken in. Hard stops with
new linings can mean
premature wear and earlier
replacement. Follow this
breaking-in guideline every
time you get new brake
linings.
.Do not tow a trailer during
break-in. See Trailer Towing
on page 9‑79 for the trailer
towing capabilities of
the vehicle and more
information.
Following break‐in, engine speed
and load can be gradually
increased.
Adjustable Throttle and
Brake Pedal
On vehicles with this feature, you
can change the position of the
throttle and brake pedals.
No adjustment to the pedals can
be made when the vehicle is in
R (Reverse) or while using cruise
control.
The control used to adjust the
pedals is located on the instrument
panel below the climate control
system.

Black plate (29,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-29
Press the bottom of the control to
move the pedals closer. Press the
top of the control to move the
pedals away.
Before you start driving, fully
press the brake pedal to confirm
the adjustment is right for you.
While driving, make only small
adjustments.
The vehicle may have a memory
function which lets pedal settings
be saved and recalled. SeePower
Seat Adjustment on page 3‑4 for
more information.Ignition Positions
The ignition switch has four different
positions.
To shift out of P (Park), the
ignition must be in ON/RUN or
ACC/ACCESSORY and the regular
brake pedal must be applied.
A (STOPPING THE ENGINE/
LOCK/OFF): When the vehicle is
stopped, turn the ignition switch to
LOCK/OFF to turn the engine off. Retained Accessory Power (RAP)
will remain active. See
Retained
Accessory Power (RAP) on
page 9‑33.
This position locks the ignition.
It also locks the transmission on
automatic transmission vehicles.
The key can be removed in
LOCK/OFF.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
In an emergency:
1. Brake using a firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to neutral. This can be done while the vehicle is
moving. After shifting to neutral,
firmly apply the brakes and steer
the vehicle to a safe location.

Black plate (30,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-30 Driving and Operating
3. Come to a complete stop, shiftto P (Park), and turn the ignition
to LOCK/OFF. On vehicles with
an automatic transmission, the
shift lever must be in P (Park) to
turn the ignition switch to the
LOCK/OFF position.
4. Set the parking brake. See Parking Brake on page 9‑51.
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
doesn't work, then the vehicle needs
service.
Notice: Using a tool to force the
key to turn in the ignition could
cause damage to the switch or
break the key. Use the correct
key, make sure it is all the way in,
and turn it only with your hand.
If the key cannot be turned by
hand, see your dealer. B (ACC/ACCESSORY):
This
position lets things like the radio
and the windshield wipers operate
while the engine is off. Use this
position if the vehicle must be
pushed or towed.
C (ON/RUN): This position can
be used to operate the electrical
accessories and to display some
instrument panel cluster warning
and indicator lights. The switch
stays in this position when the
engine is running. The transmission
is also unlocked in this position on
automatic transmission vehicles.
If you leave the key in the ACC/
ACCESSORY or ON/RUN position
with the engine off, the battery could
be drained. You may not be able to
start the vehicle if the battery is
allowed to drain for an extended
period of time. D (START):
This is the position that
starts the engine. When the engine
starts, release the key. The ignition
switch returns to ON/RUN for
driving.
A warning tone will sound when
the driver door is opened and the
ignition is in ACC/ACCESSORY or
LOCK/OFF, and the key is in the
ignition.
Starting the Engine
If the vehicle is a hybrid, see the
hybrid supplement for more
information.
Move the shift lever to P (Park) or
N (Neutral). The engine will not start
in any other position. To restart the
engine when the vehicle is already
moving, use N (Neutral) only.

Black plate (31,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-31
Notice:Do not try to shift to
P (Park) if the vehicle is moving.
If you do, you could damage the
transmission. Shift to P (Park)
only when the vehicle is stopped.
Starting Procedure
1. With your foot off the accelerator pedal, turn the ignition to START.
When the engine starts, let go of
the key. The idle speed will go
down as the engine warms.
Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently to allow the
oil to warm up and lubricate all
moving parts.
The vehicle has a
Computer-Controlled Cranking
System. This feature assists in
starting the engine and protects
components. If the ignition key is
turned to the START position,
and then released when the
engine begins cranking, the
engine will continue cranking
for a few seconds or until the vehicle starts. If the engine does
not start and the key is held in
START, cranking will be stopped
after 15 seconds to prevent
cranking motor damage. To
prevent gear damage, this
system also prevents cranking if
the engine is already running.
Engine cranking can be stopped
by turning the ignition switch
to the ACC/ACCESSORY or
LOCK/OFF position.
When the Low Fuel warning
lamp is on and the FUEL LEVEL
LOW message is displayed in
the Driver Information Center
(DIC), the Computer‐Controlled
Cranking System is disabled
to prevent possible vehicle
component damage. When this
happens, hold the ignition switch
in the START position to
continue engine cranking.
Notice: Cranking the engine for
long periods of time, by returning
the key to the START position
immediately after cranking has
ended, can overheat and damage the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start
after 5‐10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with
too much gasoline. Try pushing
the accelerator pedal all the
way to the floor and holding it
there as you hold the key in
START for up to a maximum
of 15 seconds. Wait at least
15 seconds between each try, to
allow the cranking motor to cool
down. When the engine starts,
let go of the key and accelerator.
If the vehicle starts briefly but
then stops again, repeat these
steps. This clears the extra
gasoline from the engine.
Do not race the engine
immediately after starting it.

Black plate (32,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-32 Driving and Operating
Operate the engine and
transmission gently until the
oil warms up and lubricates all
moving parts.
Notice: The engine is designed
to work with the electronics in
the vehicle. If you add electrical
parts or accessories, you could
change the way the engine
operates. Before adding electrical
equipment, check with your
dealer. If you do not, the engine
might not perform properly. Any
resulting damage would not be
covered by the vehicle warranty.Engine Heater
The engine coolant heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions
at or below −18°C (0°F). Vehicles
with an engine heater should be
plugged in at least four hours before
starting. An internal thermostat in
the plug-end of the cord may exist
which will prevent engine coolant
heater operation at temperatures
above −18°C (0°F).
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap
the electrical cord. The cord
is secured to the Engine
Compartment Fuse Block
with a clip. Carefully remove
the wire tie which secures the
electrical cord. Do not cut the
electrical cord. 3. Plug the cord into a normal,
grounded 110-volt AC outlet.
{WARNING
Plugging the cord into an
ungrounded outlet could cause an
electrical shock. Also, the wrong
kind of extension cord could
overheat and cause a fire. You
could be seriously injured. Plug
the cord into a properly grounded
three-prong 110-volt AC outlet.
If the cord will not reach, use a
heavy-duty three-prong extension
cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep
it away from moving engine
parts. If you do not, it could be
damaged.

Black plate (33,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-33
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Retained Accessory
Power (RAP)
The following vehicle accessories
can be used for up to 10 minutes
after the engine is turned off:
.Audio System
.Power Windows
.OnStar System (if equipped)
.Sunroof (if equipped)
These features work when the
key is in ON/RUN or ACC/
ACCESSORY. Once the key is
turned from ON/RUN to LOCK/OFF,
the windows and sunroof continue
to work up to 10 minutes until any
door is opened. The radio continues
to work for up to 10 minutes or until
the driver door is opened.
Shifting Into Park
{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. If you have left the engine
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle
will not move, even when you are
on fairly level ground, use the
steps that follow. If you have a
four-wheel drive transfer case
with a N (Neutral) position, and
the transfer case is in N (Neutral),
the vehicle will be free to roll,
even if the shift lever is in
P (Park). So, be sure the transfer
case is in a drive gear —not in
N (Neutral). If you are pulling a
(Continued)
WARNING (Continued)
trailer, seeDriving Characteristics
and Towing Tips on page 9‑75.
Always set the parking brake.
1. Hold the brake pedal down, then set the parking brake.
See Parking Brake on page 9‑51
for more information.
2. Move the shift lever into the P (Park) position by pulling the
shift lever toward you and
moving it up as far as it will go.
3. Be sure the transfer case is in a drive gear —not in N (Neutral).
4. Turn the ignition key to LOCK/OFF.
5. Remove the key and take it with you. If you can leave the vehicle
with the ignition key in your
hand, the vehicle is in P (Park).