2012 GMC ACADIA tow

Black plate (29,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-29
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 park brake pedal.
If the parking brake is not released
when you begin to drive, the brake
system warning light will be on 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 9‑45.Brake Assist
This vehicle 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.
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)
This vehicle has 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 automatically
activated. 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
to ensure that there is no rolling.
The brakes will automatically
release when the accelerator pedal
is applied within the two‐second
window. 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).

Black plate (35,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-35
PARK ASST BLOCKED SEE
OWNERS MANUAL:This
message can occur under the
following conditions:
.The ultrasonic sensors are not
clean. Keep the vehicle's rear
bumper free of mud, dirt, snow,
ice, and slush. For cleaning
instructions, see Exterior Care
on page 10‑86.
.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 an object was
hanging out of the liftgate during
the last drive cycle. Once the
object is removed, URPA will
return to normal operation.
.A tow bar is attached to the
vehicle.
.The bumper is damaged.
Take the vehicle to your dealer
to repair the system.
.Other conditions, such as
vibrations from a jackhammer or
the compression of air brakes on
a very large truck, are affecting
system performance.
Rear Vision
Camera (RVC)
The vehicle may have a rear vision
camera system. Read this entire
section before using it.
{WARNING
The RVC system does not display
pedestrians, bicyclists, animals,
or any other object located
outside the camera's field of view,
below the bumper, or under the
vehicle.
(Continued)
WARNING (Continued)
Do not back the vehicle using
only the RVC screen or by
using the screen during longer,
higher speed backing maneuvers,
or where there could be
cross-traffic. Perceived distances
may be different from actual
distances.
Failure to use proper care before
backing may result in injury,
death, or vehicle damage. Always
check before backing by checking
behind and around the vehicle.
Vehicles without Navigation
System
The rear vision camera system is
designed to help the driver when
backing up by displaying a view
of the area behind the vehicle.

Black plate (44,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-44 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 (45,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-45
For information on towing a disabled
vehicle, seeTowing the Vehicle on
page 10‑82. For information on
towing the vehicle behind another
vehicle such as a motor home, see
Recreational Vehicle Towing on
page 10‑82.
Driving Characteristics
and Towing Tips
{WARNING
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
(Continued)
WARNING (Continued)
For example, if the trailer is too
heavy, the brakes may not work
well—or even at all. The driver
and passengers could be
seriously injured. The vehicle may
also be damaged; the resulting
repairs would not be covered by
the vehicle warranty. Pull a trailer
only if all the steps in this section
have been followed. Ask your
dealer for advice and information
about towing a trailer with the
vehicle.
The vehicle can tow a trailer
when equipped with the proper
trailer towing equipment. For trailering capacity, see
Trailer
Towing on page 9‑49. Trailering
changes handling, acceleration,
braking, durability and fuel
economy. With the added weight,
the engine, transmission, wheel
assemblies and tires are forced to
work harder and under greater
loads. The trailer also adds wind
resistance, increasing the pulling
requirements. For safe trailering,
correctly use the proper trailering
equipment.
The following information has
important trailering tips and rules
for your safety and that of your
passengers. Read this section
carefully before pulling a trailer.

Black plate (46,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-46 Driving and Operating
Pulling a Trailer
Here are some important points:
.There are many laws, including
speed limit restrictions that apply
to trailering. Check for legal
requirements.
.Consider using sway control.
SeeTowing Equipment on
page 9‑51.
.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 reduces wear
on the vehicle.
.The vehicle can tow in D (Drive).
Use a lower gear if the
transmission shifts too often.
See “Tow/Haul Mode” later in
this section.
.Obey speed limit restrictions
when towing a trailer.
.The vehicle is designed primarily
as a passenger and load
carrying vehicle. If a trailer is
towed, the vehicle will require
more frequent maintenance due
to the additional load.
Driving with a Trailer
Towing a trailer requires experience.
Get familiar with handling and
braking with the added trailer
weight. The vehicle is now longer
and not as responsive as the
vehicle is by itself.
Check all trailer hitch parts and
attachments, safety chains,
electrical connectors, lamps, tires
and mirror adjustments. If the trailer
has electric brakes, start the vehicle
and trailer moving and then apply
the trailer brake controller by hand
to be sure the brakes are working. During the trip, check regularly to be
sure that the load is secure, and the
lamps and trailer brakes are working
properly.
Towing with a Stability Control
System
When towing, the sound of the
stability control system might be
heard. The system is reacting to the
vehicle movement caused by the
trailer, which mainly occurs during
cornering. This is normal when
towing heavier trailers.
Tow/Haul Mode
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. The purpose of the Tow/Haul
mode is to:
.Reduce the frequency and
improve the predictability of
transmission shifts.
.Provide the same solid shift feel
as when the vehicle is unloaded.

Black plate (47,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-47
.Improve control of vehicle speed
while requiring less throttle pedal
activity.
.Increase the charging system
voltage to assist in recharging a
battery installed in a trailer.
Press this button located on the
console to turn on and turn off the
Tow/Haul mode. SeeTow/Haul
Mode on page 9‑26.
The Tow/Haul light on the
instrument panel comes on to
indicate that Tow/Haul mode has
been selected.
Tow/Haul may be turned off by
pressing the button again, at which
time the indicator light on the
instrument panel will turn off.
The vehicle will automatically turn
off Tow/Haul every time it is started. Tow/Haul is designed to be most
effective when the vehicle and
trailer combined weight is at least
75 percent of the vehicle's Gross
Combined Weight Rating (GCWR).
See
Trailer Towing on page 9‑49.
Tow/Haul is most useful when
pulling a heavy trailer or a large or
heavy load under the following
driving conditions:
.Traveling through rolling terrain.
.Traveling in stop and go traffic.
.Traveling in busy parking lots
where improved low speed
control of the vehicle is desired.
Operating the vehicle in Tow/Haul
when lightly loaded or with no trailer
will not cause damage but there is
no benefit. Such a selection when
unloaded may result in unpleasant
engine and transmission driving
characteristics and reduced fuel
economy.
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 situations
that require heavy braking and
sudden turns.
Passing
More passing distance is needed
when towing a trailer. Because the
rig is longer, it is necessary to go
farther beyond the passed vehicle
before returning to the lane.
Backing Up
Hold the bottom of the steering
wheel with one hand. To move
the trailer to the left, move that
hand to the left. To move the trailer
to the right, move your hand to
the right. Always back up slowly
and, if possible, have someone
guide you.

Black plate (48,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-48 Driving and Operating
Making Turns
Notice:Making very sharp turns
while trailering could cause the
trailer to come in contact with the
vehicle. The vehicle could be
damaged. Avoid making very
sharp turns while trailering.
When turning with a trailer, make
wider turns than normal so the
trailer will not strike soft shoulders,
curbs, road signs, trees or other
objects. Use the turn signal well in
advance and avoid jerky or sudden
maneuvers.
Turn Signals When Towing a
Trailer
The turn signal indicators on the
instrument panel flash whenever
signaling a turn or lane change.
Properly hooked up, the trailer
lamps also flash, telling other
drivers the vehicle is turning,
changing lanes or stopping. When towing a trailer, the arrows on
the instrument panel flash for turns
even if the bulbs on the trailer are
burned out. Check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower
gear before starting down a long or
steep downgrade. If the
transmission is not shifted down, the
brakes might have to be used
so much that they would get hot and
no longer work well. See
“Automatic
Engine Grade Braking” within
Tow/Haul Mode on page 9‑26.
The vehicle can tow in D (Drive).
Use a lower gear if the transmission
shifts too often.
When towing at high altitude on
steep uphill grades, engine coolant
will boil at a lower temperature than
at normal altitudes. If the engine is
turned off immediately after towing
at high altitude on steep uphill
grades, the vehicle may show
signs similar to engine overheating. To avoid this, let the engine run
while parked, preferably on level
ground, with the transmission in
P (Park) for a few minutes before
turning the engine off. If the
overheat warning comes on, see
Engine Overheating on page 10‑18.
On a long uphill grade, shift down
and reduce the vehicle speed to
around 88 km/h (55 mph) to reduce
the possibility of the engine and the
transmission overheating.
Parking on Hills
{WARNING
Parking the vehicle on a hill
with the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.

Black plate (49,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-49
If parking the rig on a hill:
1. Press the brake pedal, butdo not shift into P (Park) yet.
Turn the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the brake pedal
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake
and shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
1.1. Start the engine.
1.2. Shift into a gear.
1.3. Release the parking brake.
2. Let up on the brake pedal. 3. Drive slowly until the trailer is
clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer.
See Maintenance Schedule on
page 11‑3. Things that are
especially important in trailer
operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system and
brake system. Inspect these before
and during the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See Engine Overheating
on page 10‑18.
Trailer Towing
Three important considerations
have to do with weight:
.The weight of the trailer
.The weight of the trailer tongue
.The total weight on the vehicle's
tires
Weight of the Trailer
How heavy can a trailer safely be?
Speed, altitude, road grades,
outside temperature, special
equipment, and the amount of
tongue weight the vehicle can carry
must be considered. See “Weight of
the Trailer Tongue” later in this
section for more information.
Maximum trailer weight is calculated
assuming only the driver is in the
tow vehicle and it has all the
required trailering equipment.
The weight of additional optional
equipment, passengers and cargo in
the tow vehicle must be subtracted
from the maximum trailer weight.