GMC ACADIA 2009 Owner's Manual
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Safety Chains
Always attach chains between the
vehicle and the trailer. Cross
the safety chains under the tongue
of the trailer to help prevent the
tongue from contacting the road
if it becomes separated from
the hitch. Instructions about safety
chains may be provided by the
hitch manufacturer or by the
trailer manufacturer. Follow the
manufacturer’s recommendation
for attaching safety chains and do
not attach them to the bumper.
Always leave just enough slack
so the rig can turn. Never allow
safety chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 1,000 lbs (450 kg) needs
to have its own brake system that is
adequate for the weight of the
trailer. Be sure to read and follow
the instructions for the trailer brakes
so they are installed, adjusted
and maintained properly.Because the vehicle has antilock
brakes, do not try to tap into
the vehicle’s hydraulic brake system.
If you do, both brake systems will
not work well, or at all.
Driving with a Trailer
Towing a trailer requires a certain
amount of experience. Get to know
the rig before setting out for the open
road. Get acquainted with the feel of
handling and braking with the added
weight of the trailer. And always keep
in mind that the vehicle you are
driving is now longer and not as
responsive as the vehicle is by itself.
Before starting, 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. This checks the electrical
connection at the same time.During the trip, check occasionally
to be sure that the load is secure,
and that the lamps and any
trailer brakes are still working.
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
much farther beyond the passed
vehicle before returning to the lane.
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Backing Up
Hold the bottom of the steering
wheel with one hand. Then, 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. Do this so
the trailer won’t strike soft shoulders,
curbs, road signs, trees or other
objects. Avoid jerky or sudden
maneuvers. Signal well in advance.
Turn Signals When Towing a
Trailer
The arrows on the instrument panel
ash whenever signaling a turn
or lane change. Properly hooked up,
the trailer lamps also ash, telling
other drivers the vehicle is turning,
changing lanes or stopping.
When towing a trailer, the arrows on
the instrument panel ash for turns
even if the bulbs on the trailer are
burned out. For this reason you may
think other drivers are seeing the
signal when they are not. It is
important to check occasionally to be
sure the trailer bulbs are still working.
Driving on Grades
Because of the added load of the
trailer, the vehicle’s engine may
overheat on hot days, when going
up a long or steep grade with a
trailer. If the engine coolant
temperature gage indicates
overheating, turn off the air
conditioning to reduce engine load,
pull off the road and stop in a
safe spot. 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.
Reduce speed and shift to a lower
gearbeforestarting 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.
On a long uphill grade, shift down
and reduce the vehicle speed
to around 55 mph (88 km/h) to
reduce the possibility of the engine
and the transmission overheating.
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Tow/Haul Mode
Tow/Haul is a feature that 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 when pulling
a heavy trailer or a large or
heavy load.
Provide the same solid shift feel
when pulling a heavy trailer or a
large or heavy load as when
the vehicle is unloaded.
Improve control of vehicle speed
while requiring less throttle pedal
activity when pulling a heavy
trailer or a large or heavy load.
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.
The Tow/Haul light on the
instrument panel will come 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 Weight of the Trailerearlier in this section. Tow/Haul is
most useful under the following
driving conditions:
When pulling a heavy trailer or a
large or heavy load through
rolling terrain.
When pulling a heavy trailer or a
large or heavy load in stop and
go traffic.
When pulling a heavy trailer or a
large or heavy load 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
at all will not cause damage.
However, there is no bene t to the
selection of Tow/Haul when the
vehicle is unloaded. Such a selection
when unloaded may result in
unpleasant engine and transmission
driving characteristics and reduced
fuel economy. Tow/Haul is
recommended only when pulling a
heavy trailer or a large or heavy load.
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Parking on Hills
{CAUTION
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 at 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 the transmission 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, and
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.
SeeScheduled Maintenance on
page 6-3for more information.
Things that are especially important
in trailer operation are automatic
transmission uid, engine oil,
axle lubricant, belts, cooling system
and brake system. It is a good
idea to inspect these before and
during the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Trailer Wiring Harness
The vehicle is equipped with the
following wiring harness for towing
a trailer.
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Basic Trailer Wiring
The trailer wiring harness, with a
seven-pin connector, is located
at the rear of the vehicle and is
tied to the vehicle’s frame.
The harness connector can be
plugged into a seven-pin universal
heavy-duty trailer connector
available through your
dealer/retailer.
The seven-wire harness contains
the following trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn
Signal
Brown: Taillamps
Black: Ground
Light Green: Back-up Lamps
Red/Black: Battery Feed
Dark Blue: Trailer Brake*
*The fuse for this circuit is installed
in the underhood electrical center,
but the wires are not connected.
They should be connected by your
dealer/retailer or a quali ed
service center.
If the back-up lamp circuit is not
functional, contact your
dealer/retailer.If a remote (non-vehicle) battery is
being charged, press the Tow/Haul
mode switch located on the center
console near the climate controls.
This will boost the vehicle system
voltage and properly charge the
battery. If the trailer is too light for
Tow/Haul mode, turn on the
headlamps (Non-HID only) as a
second way to boost the vehicle
system and charge the battery.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. SeeEngine Overheating
on page 5-21.
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✍NOTES
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