2011 GMC ACADIA tow

Black plate (36,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-36 Driving and Operating
How the System Works
URPA comes on automatically
when the shift lever is moved into
R (Reverse). A single tone sounds
to indicate the system is working.
URPA operates only at speeds less
than 8 km/h (5 mph).
An obstacle is indicated by audible
beeps. The interval between the
beeps becomes shorter as the
vehicle gets closer to the obstacle.
When the distance is less than
30 cm (12 in) the beeps are
continuous.
To be detected, objects must be at
least 25.4 cm (10 in) off the ground
and below liftgate level. Objects
must also be within 2.5 m (8 ft) from
the rear bumper. This distance may
be less during warmer or humid
weather.
The system can be disabled through
the Driver Information Center (DIC).
See“Park Assist” underVehicle
Personalization (With DIC Buttons)
on page 5‑47 for more information.
When the System Does Not
Seem to Work Properly
If the URPA system does not
activate due to a temporary
condition, the message PARK
ASSIST OFF or PARK ASST
BLOCKED SEE OWNERS
MANUAL will be displayed
on the DIC.
SERVICE PARK ASSIST: If this
message occurs, take the vehicle
to your dealer to repair the system.
PARK ASSIST OFF: This message
occurs if the driver disables the
system.
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 10‑90.
.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
liftgate during the last drive
cycle. Once the attached object
is removed, 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 may affect
system performance, such as
vibrations from a jackhammer or
the compression of air brakes on
a very large truck.

Black plate (46,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-46 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 (47,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-47
For information on towing a disabled
vehicle, seeTowing the Vehicle on
page 10‑87. For information on
towing the vehicle behind another
vehicle such as a motor home, see
Recreational Vehicle Towing on
page 10‑87.
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.
For example, if the trailer is too
heavy, the brakes may not work
(Continued)
WARNING (Continued)
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 9‑52. 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 (48,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-48 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 9‑54.
.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.

Black plate (49,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-49
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.
.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 9‑28.
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 9‑52.
Tow/Haul is most useful when
pulling a heavy trailer or a large
or heavy load under the following
driving conditions:.Travelling through rolling terrain.
.Travelling in stop and go traffic.
.Travelling 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.

Black plate (50,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-50 Driving and Operating
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.
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” withinTow/
Haul Mode on page 9‑28.
The vehicle can tow in D (Drive).
Use a lower gear if the transmission
shifts too often.

Black plate (51,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-51
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 10‑19.
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.
If parking the rig on a hill:
1. Press the brake pedal, but do 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:
.Start the engine.
.Shift into a gear.
.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.

Black plate (52,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-52 Driving and Operating
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule
or Index for more information.
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. SeeEngine Overheating
on page 10‑19.
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.
Use the following chart to determine
how much the vehicle can weigh,
based upon the vehicle model and
options.