Black plate (12,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-12 Driving and Operating
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. SeeTires on
page 10‑48.
.Turn off cruise control.
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 the interior
temperature cool.
.Keep your eyes moving —scan
the road ahead and to the sides.
.Check the rearview mirror and
vehicle instruments often.
Black plate (13,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-13
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. 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.
.Be alert on top of hills,
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.
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.
Black plate (14,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-14 Driving and Operating
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.
TheAntilock Brake System (ABS)
on page 9‑44 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 13‑5.
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)
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.
.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 Systems” in
the Index.
(Continued)
Black plate (15,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-15
WARNING (Continued)
For more information about
carbon monoxide, seeEngine
Exhaust on page 9‑30.
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.
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.
Black plate (17,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-17
Tire and Loading Information
Label
Label Example
A vehicle specific Tire and
Loading Information label is
attached to the center pillar
(B-pillar). With the driver door
open, you will find the label
attached below the door lock
post (striker). The tire and
loading information label shows
the number of occupant seatingpositions (A), and the maximum
vehicle capacity weight (B) in
kilograms and pounds.
The Tire and Loading
Information label also shows the
size of the original equipment
tires (C) and the recommended
cold tire inflation pressures (D).
For more information on tires
and inflation see
Tires on
page 10‑48 and
Tire Pressure on
page 10‑56.
There is also important loading
information on the vehicle
Certification/Tire label. It tells
you the Gross Vehicle Weight
Rating (GVWR) and the Gross
Axle Weight Rating (GAWR) for
the front and rear axles. See
“Certification/Tire Label” later in
this section. Steps for Determining Correct
Load Limit
1.Locate the statement
“The combined weight of
occupants and cargo should
never exceed XXX kg or
XXX lbs”
on your vehicle's
placard.
2.Determine the combined
weight of the driver and
passengers that will be riding
in your vehicle.
3.Subtract the combined
weight of the driver and
passengers from XXX kg or
XXX lbs.
4.The resulting figure equals
the available amount of cargo
and luggage load capacity.
For example, if the “XXX”
amount equals 1400 lbs and
there will be five 150 lb
passengers in your vehicle,
Black plate (19,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-19
Example 3
A. Vehicle Capacity Weight for Example 3 = 453 kg (1,000 lbs)
B. Subtract Occupant Weight @ 91 kg (200 lbs) × 5 = 453 kg
(1,000 lbs)
C. Available Cargo Weight = 0 kg (0 lbs)
Refer to your vehicle's tire and
loading information label for
specific information about
your vehicle's capacity weight
and seating positions. The combined weight of the
driver, passengers, and cargo
should never exceed your
vehicle's capacity weight.
Certification/Tire Label
A vehicle specific Certification/
Tire label is found on the rear
edge of the driver door. The
label shows the size of your
vehicle's original tires and the
inflation pressures needed to
obtain the gross weight capacity
of your vehicle. This is called
Gross Vehicle Weight Rating
(GVWR). The GVWR includes
the weight of the vehicle, all
occupants, fuel, and cargo.
The Certification/Tire label also
tells you the maximum weights
for the front and rear axles,
called Gross Axle Weight Rating
(GAWR). To find out the actual
loads on your front and rear
axles, you need to go to a weigh
station and weigh your vehicle.
Your dealer can help you with
this. Be sure to spread out your
load equally on both sides of the
centerline.
Never exceed the GVWR for
your vehicle, or the GAWR for
either the front or rear axle.
The Certification/Tire label also
contains information about your
Front Axle Reserve Capacity.
Black plate (34,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-34 Driving and Operating
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. The
transmission constantly makes
adjustments to improve vehicle
performance according to how the
vehicle is being used, such as
with a heavy load or when the
temperature changes. During this
adaptive shift control process,
shifting might feel different as the
transmission determines the best
settings.
When temperatures are very cold,
shifting could be delayed providing
more stable shifts until the engine
warms up. Shifts could be more
noticeable with a cold transmission.
This difference in shifting is normal.
M (Manual Mode):This position
lets drivers select the range of gears
appropriate for current driving
conditions. If the vehicle has this feature, see
“Range Selection
Mode” underManual Mode on
page 9‑35.
3 (Third): This position is also used
for normal driving. It reduces vehicle
speed more than D (Drive) without
using the brakes. You might choose
3 (Third) instead of D (Drive) when
driving on hilly, winding roads, when
towing a trailer, so there is less
shifting between gears and when
going down a steep hill.
2 (Second): This position reduces
vehicle speed even more than
3 (Third) without using the brakes.
You can use 2 (Second) on hills.
It can help control vehicle speed as
you go down steep mountain roads,
but then you would also want to use
the brakes off and on.
If you manually select 2 (Second) in
an automatic transmission, the
transmission will start in
second gear. You can use this
feature for reducing the speed of the rear wheels when you are trying to
start the vehicle from a stop on
slippery road surfaces.
1 (First):
This position reduces
vehicle speed without using the
brakes. You can use it for major/
severe downgrades and off-road
driving where the vehicle would
otherwise accelerate due to
steepness of grade. When you shift
to 1 (First) it provides the lowest
gear appropriate to the vehicle's
current road speed and continues to
downshift as the vehicle slows,
eventually downshifting to
1 (First) gear.
Notice: Spinning the tires or
holding the vehicle in one
place on a hill using only the
accelerator pedal may damage
the transmission. The repair will
not be covered by the vehicle
warranty. If you are stuck, do not
spin the tires. When stopping on
a hill, use the brakes to hold the
vehicle in place.
Black plate (35,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-35
Manual Mode
Range Selection Mode
(Hydra-Matic®6-Speed
Transmission)
Base Trim Shown (Uplevel Similar)
The vehicle may have a Range
Selection Mode. The Range
Selection Mode helps control the
vehicle's transmission and vehicle
speed while driving down hill or
towing a trailer by letting you select
a desired range of gears.
To use this feature, do the following:
1. Move the shift lever to M (Manual Mode). 2. Press the plus/minus buttons,
located on the steering column
shift lever, to select the desired
range of gears for the current
driving conditions.
When M (Manual Mode) is selected
a number displays next to the M,
indicating the current gear.
This number is the highest gear that
can be used. However, the vehicle
can automatically shift to lower
gears as it adjusts to driving
conditions. This means that all
gears below that number are
available. When 5 (Fifth) is selected,
1 (First) through 5 (Fifth) gears are
automatically shifted by the vehicle,
but 6 (Sixth) cannot be used until
the plus/minus button located on the
steering column lever is used to
change to the gear.
Grade Braking is not available when
Range Selection Mode is active.
See Tow/Haul Mode on page 9‑36. While using Range Selection Mode,
Cruise Control and the Tow/Haul
Mode can be used.
Notice:
Spinning the tires or
holding the vehicle in one place
on a hill using only the
accelerator pedal may damage
the transmission. The repair will
not be covered by the vehicle
warranty. If you are stuck, do not
spin the tires. When stopping on
a hill, use the brakes to hold the
vehicle in place.
Low Traction Mode
If the vehicle has the Hydra-Matic®
6-Speed Automatic Transmission, it
has a Low Traction Mode that
assists in vehicle acceleration when
road conditions are slippery, such
as with ice or snow. While the
vehicle is at a stop, select the
second gear range using Range
Selection Mode. This will limit
torque to the wheels after it detects
wheel slip, preventing the tires from
spinning.