2011 GMC YUKON XL brake

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 (15,1)GMC Yukon/Yukon XL Owner Manual - 2011
Driving and Operating 9-15
Vehicles are much more likely to
stall when going uphill, but if it
happens when going downhill:
1. Stop the vehicle by applying theregular brakes and apply the
parking brake.
2. Shift to P (Park) and, while still braking, restart the engine.
3. Shift back to a low gear, release the parking brake, and drive
straight down.
4. If the engine will not start, get out and get help.
Driving Across an Incline
An off-road trail will probably go
across the incline of a hill. To decide
whether to try to drive across the
incline, consider the following:
{WARNING
Driving across an incline that is
too steep will make your vehicle
roll over. You could be seriously
(Continued)
WARNING (Continued)
injured or killed. If you have any
doubt about the steepness of the
incline, do not drive across it.
Find another route instead.
.A hill that can be driven straight
up or down might be too steep
to drive across. When going
straight up or down a hill, the
length of the wheel base —the
distance from the front wheels to
the rear wheels —reduces the
likelihood the vehicle will tumble
end over end. But when driving
across an incline, the narrower
track width —the distance
between the left and right
wheels —might not prevent the
vehicle from tilting and rolling
over. Driving across an incline
puts more weight on the downhill
wheels which could cause a
downhill slide or a rollover.
.Surface conditions can be a
problem. Loose gravel, muddy
spots, or even wet grass can
cause the tires to slip sideways,
downhill. If the vehicle slips
sideways, it can hit something
that will trip it —a rock, a rut,
etc. —and roll over.
.Hidden obstacles can make the
steepness of the incline even
worse. If you drive across a rock
with the uphill wheels, or if the
downhill wheels drop into a rut
or depression, the vehicle can tilt
even more.
For these reasons, carefully
consider whether to try to drive
across an incline. Just because the
trail goes across the incline does
not mean you have to drive it. The
last vehicle to try it might have
rolled over.

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 (18,1)GMC Yukon/Yukon XL Owner Manual - 2011
9-18 Driving and Operating
Driving on Wet Roads
Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep‐standing or flowing water.
{WARNING
Wet brakes can cause crashes.
They might not work as well in
a quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.(Continued)
WARNING (Continued)
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under the vehicle's
tires so they actually ride on the
water. This can happen if the road
is wet enough and you are going
fast enough. When the vehicle is
hydroplaning, it has little or no
contact with the road. There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping
equipment in good shape.
.Keep the windshield washer fluid
reservoir filled.
.Have good tires with proper
tread depth. See
Tires on
page 10‑48.
.Turn off cruise control.

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 (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.