2011 GMC SIERRA trailer

Black plate (50,1)GMC Sierra Owner Manual - 2011
9-50 Driving and Operating
Manual Mode
Range Selection Mode
(Allison®Transmission or
Hydra-Matic®6-Speed
Transmission)
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 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 9‑51.
While using Range Selection Mode,
Cruise Control and the Tow/Haul
Mode can be used.
If the vehicle has an exhaust
brake, it can also be used, but will
not automatically downshift the
transmission. See Exhaust Brake in
the Duramax Diesel supplement.
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 (69,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-69
Braking in Emergencies
ABS allows the driver 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 5‑27.
Notice: Driving with the parking
brake on can overheat the brake
system and cause premature
wear or damage to brake system
parts. Make sure that the parking
brake is fully released and the
brake warning light is off before
driving.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the parking brake pedal.
If the parking brake is not released
when you begin to drive, the brake
system warning light will flash and a
chime will sound warning you that
the parking brake is still on.
If you are towing a trailer and
are parking on a hill, see Driving
Characteristics and Towing Tips on
page 9‑91.
Brake Assist (Except
With 4.3L V6 Engine)
If this vehicle has StabiliTrak®, it
also has a Brake Assist feature
designed to assist the driver in
stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement
the power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle.
The stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.

Black plate (70,1)GMC Sierra Owner Manual - 2011
9-70 Driving and Operating
Minor brake pedal pulsation or
pedal movement during this time
is normal and the driver should
continue to apply the brake pedal
as the driving situation dictates
The Brake Assist feature will
automatically disengage when
the brake pedal is released or
brake pedal pressure is quickly
decreased.
Hill Start Assist (HSA)
2500 and 3500 series vehicles with
StabiliTrak have a Hill Start Assist
(HSA) feature, which may be useful
when the vehicle is stopped on a
grade. This feature is designed to
prevent the vehicle from rolling,
either forward or rearward, during
vehicle drive off. After the driver
completely stops and holds the
vehicle in a complete standstill on
a grade, HSA will be automaticallyactivated. During the transition
period between when the driver
releases the brake pedal and starts
to accelerate to drive off on a grade,
HSA holds the braking pressure
for a maximum of two seconds
to ensure that there is no rolling.
The brakes will automatically
release when the accelerator pedal
is applied within the two‐second
window. If the vehicle is equipped
with the Integrated Trailer Brake
Control (ITBC) system, HSA may
also apply the trailer brakes. It will
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
StabiliTrak®System
The vehicle may have a vehicle
stability enhancement system called
StabiliTrak
®. It is an advanced
computer-controlled system that
assists the driver with directional
control of the vehicle in difficult
driving conditions.
StabiliTrak activates when the
computer senses a discrepancy
between the intended path and
the direction the vehicle is actually
traveling. StabiliTrak selectively
applies braking pressure at any one
of the vehicle's brakes to assist the
driver with keeping the vehicle on
the intended path.

Black plate (73,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-73
The traction control system may
activate on dry or rough roads
or under conditions such as
heavy acceleration while turning
or abrupt upshifts/downshifts of the
transmission. When this happens,
a reduction in acceleration may be
noticed, or a noise or vibration may
be heard. This is normal.
If cruise control is being used when
the system activates, the StabiliTrak
light will flash and cruise control will
automatically disengage. Cruise
control may be reengaged when
road conditions allow. SeeCruise
Control on page 9‑73.
StabiliTrak may also turn off
automatically if it determines that
a problem exists with the system.
If the problem does not clear itself
after restarting the vehicle, see your
dealer for service. 2500 and 3500 series vehicles
with StabiliTrak have a Trailer Sway
Control (TSC) feature. See
Trailer
Sway Control (TSC) on page 9‑124.
2500 and 3500 series vehicles
with StabiliTrak have a Hill Start
Assist (HSA) feature. See Hill Start
Assist (HSA) on page 9‑70.
Adding non‐dealer accessories can
affect the vehicle's performance.
See Accessories and Modifications
on page 10‑3.
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.
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.
For vehicles 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).

Black plate (78,1)GMC Sierra Owner Manual - 2011
9-78 Driving and Operating
.The park assist sensors are
covered by frost or ice. Frost or
ice can form around and behind
the sensors and may not always
be seen; this can occur after
washing the vehicle in cold
weather. The message may
not clear until the frost or ice
has melted.
.A trailer was attached to the
vehicle, or a bicycle or an object
was hanging out of the tailgate
during the last drive cycle. Once
the attached object is removed
and the tailgate is raised, URPA
will return to normal operation.
.A tow bar is attached to the
vehicle.
.The vehicle's bumper is
damaged. Take the vehicle to
your dealer to repair the system.
.Other conditions are affecting
system performance. Examples
of this are vibrations from a
jackhammer or the compression
of air brakes on a very large
truck.
Rear Vision
Camera (RVC)
This vehicle may have a Rear
Vision Camera (RVC) system. Read
this entire section before using it.
{WARNING
The Rear Vision Camera (RVC)
system does not replace driver
vision. RVC does not:
.Detect objects that are
outside the camera's field
of view, below the bumper,
or underneath the vehicle.
.Detect children, pedestrians,
bicyclists, or pets.
Do not back the vehicle by only
looking at the RVC screen, or use
the screen during longer, higher (Continued)
WARNING (Continued)
speed backing maneuvers or
where there could be cross-traffic.
Your judged distances using the
screen will differ from actual
distances.
If you do not use proper care
before backing up, you could
hit a vehicle, child, pedestrian,
bicyclist, or pet, resulting in
vehicle damage, injury, or death.
Even though the vehicle has
the RVC system, always check
carefully before backing up by
checking behind and around the
vehicle.

Black plate (90,1)GMC Sierra Owner Manual - 2011
9-90 Driving and Operating
Filling a Portable Fuel
Container
{WARNING
Never fill a portable fuel container
while it is in the vehicle. Static
electricity discharge from the
container can ignite the fuel
vapor. You can be badly burned
and the vehicle damaged if this
occurs. To help avoid injury to
you and others:
.Dispense fuel only into
approved containers.
.Do not fill a container while
it is inside a vehicle, in a
vehicle's trunk, pickup bed,
or on any surface other than
the ground.(Continued)
WARNING (Continued)
.Bring the fill nozzle in contact
with the inside of the fill
opening before operating
the nozzle. Contact should
be maintained until the filling
is complete.
.Do not smoke while
pumping fuel.
.Do not use a cellular phone
while pumping fuel.
Towing
General Towing
Information
Only use towing equipment that
has been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle for towing a trailer.
See the following trailer towing
information in this section:
.For information on driving
while towing a trailer, see
“Driving Characteristics and
Towing Tips.”
.For maximum vehicle and trailer
weights, see“Trailer Towing.”
.For information on equipment
to tow a trailer, see “Towing
Equipment.”

Black plate (91,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-91
For information on towing a disabled
vehicle, seeTowing the Vehicle on
page 10‑103. For information on
towing the vehicle behind another
vehicle such as a motor home, see
Recreational Vehicle Towing on
page 10‑103.
Driving Characteristics
and Towing Tips
Pulling a Trailer
Important points for pulling a trailer:
.There are many different laws,
including speed limit restrictions,
having to do with trailering.
Make sure the rig will be legal,
not only where you live but
also where you will be driving.
A good source for this
information can be state
or provincial police.
.Consider using a sway control.
See “Hitches” underTowing
Equipment on page 9‑112.
.Do not tow a trailer at all during
the first 800 km (500 miles)
the new vehicle is driven.
The engine, axle, or other
parts could be damaged.
.During the first 800 km
(500 miles) that a trailer is
towed, do not drive over
80 km/h (50 mph) and do
not make starts at full throttle.
This helps the engine and other
parts of the vehicle wear in at
the heavier loads.
.Vehicles can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts
too often under heavy loads
and/or hilly conditions.
Important considerations that have
to do with weight:
.Weight of the trailer
.Weight of the trailer tongue
.Weight on the vehicle's tires
.Weight of the trailering
combination

Black plate (92,1)GMC Sierra Owner Manual - 2011
9-92 Driving and Operating
Driving with a Trailer
{WARNING
When towing a trailer, exhaust
gases may collect at the rear
of the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
Engine exhaust contains Carbon
Monoxide (CO) which cannot be
seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing
a trailer:
.Have the exhaust system
inspected for leaks and make
necessary repairs before
starting a trip.
.Never drive with the liftgate,
trunk/hatch, or rear-most
window open.(Continued)
WARNING (Continued)
.Fully open the air outlets
on or under the instrument
panel.
.Adjust the Climate Control
system to a setting that
brings in only outside air
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 9‑44.
Towing a trailer requires a
certain amount of experience.
The combination you are driving is
longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road. Before starting, check all trailer
hitch parts and attachments, safety
chains, electrical connectors,
lamps, tires, and mirrors. If the
trailer has electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid heavy
braking and sudden turns.