2011 GMC ACADIA trailer

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.

Black plate (53,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-53
VehicleMaximum Trailer Weight *GCWR
Front‐Wheel Drive 2,000 lbs (907 kg)7,500 lbs (3 402 kg)
Front‐Wheel Drive, V92 Trailer Towing Package 5,200 lbs (2 359 kg) 10,250 lbs (4 649 kg)
All‐Wheel Drive 2,000 lbs (907 kg)7,700 lbs (3 493 kg)
All‐Wheel Drive, V92 Trailer Towing Package 5,200 lbs (2 359 kg)10,450 lbs (4 740 kg)
*The Gross Combination Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicle and
trailer including any passengers, cargo, equipment and conversions. The GCWR for the vehicle should not be
exceeded.
Ask your dealer for our
trailering information or advice.
See Customer Assistance Offices
(U.S. and Canada) on page 13‑5
or Customer Assistance Offices
(Mexico) on page 13‑6 for more
information.
Weight of the Trailer Tongue
The tongue load (A) of any trailer is
an important weight to measure
because it affects the total gross
weight of the vehicle. The Gross
Vehicle Weight (GVW) includes
the curb weight of the vehicle,
any cargo carried in it, and the
people who will be riding in the
vehicle. If there are a lot of options, equipment, passengers or cargo in
the vehicle, it will reduce the tongue
weight the vehicle can carry, which
will also reduce the trailer weight the
vehicle can tow. If towing a trailer,
the tongue load must be added
to the GVW because the vehicle
will be carrying that weight, too.
See
Vehicle Load Limits on
page 9‑12.

Black plate (54,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-54 Driving and Operating
If a weight-carrying hitch or a
weight-distributing hitch is being
used, the trailer tongue (A) should
weigh 10‐15 percent of the total
loaded trailer weight (B).
After loading the trailer, weigh
the trailer and then the tongue,
separately, to see if the weights are
proper. If they are not, adjustments
might be made by moving some
items around in the trailer.
Trailering may be limited by the
vehicle's ability to carry tongue
weight. Tongue weight cannot
cause the vehicle to exceed theGVWR (Gross Vehicle Weight
Rating) or the RGAWR (Rear Gross
Axle Weight Rating). The effect of
additional weight may reduce the
trailering capacity more than the
total of the additional weight.
It is important that the vehicle
does not exceed any of its
ratings
—GCWR, GVWR, RGAWR,
Maximum Trailer Rating or Tongue
Weight. The only way to be sure it is
not exceeding any of these ratings
is to weigh the vehicle and trailer.
Total Weight on the Vehicle's
Tires
Inflate the vehicle's tires to the
upper limit for cold tires. These
numbers can be found on the
Certification label or see Vehicle
Load Limits on page 9‑12 for more
information. Do not go over the
GVW limit for the vehicle, or the
GAWR, including the weight of the
trailer tongue. If using a weight
distributing hitch, do not go over the
rear axle limit before applying the
weight distribution spring bars.
Towing Equipment
Hitches
It is important to have the correct
hitch equipment. Crosswinds, large
trucks going by and rough roads are
a few reasons why the right hitch is
needed.
.The rear bumper on the vehicle
is not intended for hitches.
Do not attach rental hitches
or other bumper-type hitches
to it. Use only a frame-mounted
hitch that does not attach to the
bumper.
.Will any holes be made in the
body of the vehicle when the
trailer hitch is installed? If there
are, then be sure to seal the
holes when the hitch is removed.
If the holes are not sealed,
dirt, water, and deadly carbon
monoxide (CO) from the exhaust
may get into the vehicle. See
Engine Exhaust on page 9‑24.

Black plate (55,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-55
Weight-Distributing Hitches and
Weight Carrying Hitches
A. Body-to-Ground Distance
B. Front of Vehicle
When using a weight-distributing
hitch, the hitch must be adjusted so
that the distance (A) remains the
same both before and after coupling
the trailer to the tow vehicle.
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.
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 450 kg (1,000 lbs) 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.
Trailer Wiring Harness
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.
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*

Black plate (56,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-56 Driving and Operating
*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 or a qualified service center.
If the back-up lamp circuit is not
functional, contact your dealer.
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.Electric Trailer Brake Control
Wiring Provisions
These wiring provisions for an
electric trailer brake controller
are included with the vehicle as
part of the trailer wiring package.
The instrument panel contains
blunt cut wires behind the steering
column for the electric trailer brake
controller. The harness contains
the following wires:
.Red/Black: Power Supply
.White: Brake Switch Signal
.Gray: Illumination
.Dark Blue: Trailer Brake Signal
.Black: Ground
The electric trailer brake controller
should be installed by your dealer
or a qualified service center.
Conversions and
Add-Ons
Add-On Electrical
Equipment
Notice: Do not add anything
electrical to the vehicle unless
you check with your dealer first.
Some electrical equipment can
damage the vehicle and the
damage would not be covered
by the vehicle's warranty. Some
add-on electrical equipment can
keep other components from
working as they should.
Add-on equipment can drain the
vehicle's 12‐volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle on page 3‑45 andAdding
Equipment to the Airbag-Equipped
Vehicle on page 3‑46.

Black plate (21,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Vehicle Care 10-21
If No Steam Is Coming from
the Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem may not be
too serious. Sometimes the engine
can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day
.Stops after high-speed driving
.Idles for long periods in traffic
.Tows a trailerIf the overheat warning is displayed
with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest
temperature and to the highest
fan speed. Open the windows as
necessary.
3. If in a traffic jam, shift to N (Neutral), otherwise, shift
to the highest gear while
driving —D (Drive) or L (Low).
If the temperature overheat gauge
is no longer in the overheat zone
or an overheat warning no longer
displays, the vehicle can be driven. Continue to drive the vehicle slow
for about 10 minutes. Keep a safe
vehicle distance from the car in front
of you. If the warning does not come
back on, continue to drive normally.
If the warning continues, pull
over, stop, and park the vehicle
right away.
If there is no sign of steam, idle
the engine for three minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down. Also, see
“Overheated
Engine Protection Operating Mode”
next in this section.

Black plate (22,1)GMC Acadia/Acadia Denali Owner Manual - 2011
10-22 Vehicle Care
Overheated Engine
Protection
Operating Mode
This emergency operating mode lets
the vehicle be driven to a safe place
in an emergency situation. If an
overheated engine condition exists,
an overheat protection mode which
alternates firing groups of cylinders
helps prevent engine damage. In
this mode, there is a significant loss
in power and engine performance.
The temperature gauge indicates an
overheat condition exists. Driving
extended distances and/or towing
a trailer in the overheat protection
mode should be avoided.
Notice:After driving in the
overheated engine protection
operating mode, to avoid engine
damage, allow the engine to cool
before attempting any repair.
The engine oil will be severely
degraded. Repair the cause of
coolant loss, change the oil
and reset the oil life system.
See Engine Oil on page 10‑8.
Power Steering Fluid
The power steering fluid reservoir is
located under the engine cover on
the passenger side of the vehicle.
SeeEngine Compartment Overview
on page 10‑6 for reservoir location.
When to Check Power Steering
Fluid
It is not necessary to regularly
check power steering fluid unless
you suspect there is a leak in the
system or you hear an unusual
noise. A fluid loss in this system
could indicate a problem. Have the
system inspected and repaired.
How to Check Power Steering
Fluid
To check the power steering fluid:
1. Turn the key off and let the
engine compartment cool down.
2. Remove the engine cover. See Engine Cover on page 10‑7.
3. Wipe the cap and the top of the reservoir clean.
4. Unscrew the cap and wipe the dipstick with a clean rag.
5. Replace the cap and completely tighten it.
6. Remove the cap again and look at the fluid level on the dipstick.
The fluid level should be
somewhere between MAX and
MIN line on the dipstick in room
temperature. If the fluid is on or
below MIN line, you should add
fluid close to MAX Line.