trailer GMC ACADIA 2007 Owner's Guide

The effect of additional weight may reduce your
trailering capacity more than the total of the
additional weight.
Consider the following example:
A vehicle model base weight is 5,500 lbs
(2 495 kg); 2,800 lbs (1 270 kg) at the front axle
and 2,700 lbs (1 225 kg) at the rear axle. It has
a GVWR of 7,200 lbs (3 266 kg), a RGAWR
of 4,000 lbs (1 814 kg) and a GCWR (Gross
Combination Weight Rating) of 14,000 lbs
(6 350 kg). The trailer rating should be:
You can expect tongue weight to be at least
10 percent of trailer weight (850 lbs (386 kg)) and
because the weight is applied well behind the rear
axle, the effect on the rear axle will be greater than
just the weight itself, as much as 1.5 times as much.The weight at the rear axle could be 850 lbs
(386 kg) X 1.5 = 1,275 lbs (578 kg). Since the rear
axle already weighs 2,700 lbs (1 225 kg), adding
1,275 lbs (578 kg) brings the total to 3,975 lbs
(1 803 kg). This is very close to, but within the limit
for RGAWR as well. The vehicle is set to trailer
up to 8,500 lbs (3 856 kg).
But let’s say your specic vehicle is equipped with
some of the latest options and you have a front
seat passenger and two rear seat passengers with
some luggage and gear in the vehicle as well.
You may add 300 lbs (136 kg) to the front axle
weight and 400 lbs (181 kg) to the rear axle
weight. Your vehicle now weighs:
Weight is still below 7,200 lbs (3 266 kg) and you
may think that you should subtract 700 additional
pounds (318 kg) from your trailering capacity
to stay within GCWR limits. Your maximum
trailer would only be 7,800 lbs (3 538 kg).
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You may go further and think you must limit
tongue weight to less than 1,000 lbs (454 kg) to
avoid exceeding GVWR. But, you must still
consider the effect on the rear axle. Because your
rear axle now weighs 3,100 lbs (1 406 kg), you
can only put 900 lbs (408 kg) on the rear axle
without exceeding RGAWR. The effect of tongue
weight is about 1.5 times the actual weight.
Dividing the 900 lbs (408 kg) by 1.5 leaves you
with being able to handle only 600 lbs (272 kg) of
tongue weight. Since tongue weight is usually
at least 10 percent of total loaded trailer weight,
you can expect that the largest trailer your vehicle
can properly handle is 6,000 lbs (2 721 kg).
It is important that you make sure your vehicle
does not exceed any of its ratings — GCWR,
GVWR, RGAWR, Maximum Trailer Rating
or Tongue Weight. The only way to be sure you
are not exceeding any of these ratings is to weigh
your vehicle and trailer.Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper
limit for cold tires. You’ll nd these numbers on the
Certication/Tire label. SeeLoading Your Vehicle
on page 361. Then be sure you don’t go over the
GVW limit for your vehicle, including the weight of
the trailer tongue.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough
roads are a few reasons why you’ll need the
right hitch. Here are some rules to follow:
The rear bumper on your 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 you have to make any holes in the body of
your vehicle when you install a trailer hitch?
If you do, then be sure to seal the holes later
when you remove the hitch. If you don’t seal
them, deadly carbon monoxide (CO) from your
exhaust can get into your vehicle. SeeEngine
Exhaust on page 138. Dirt and water can, too.
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Safety Chains
You should always attach chains between your
vehicle and your trailer. Cross the safety
chains under the tongue of the trailer so that the
tongue will not drop to 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 you
can turn with your rig. And, never allow safety
chains to drag on the ground.
Trailer Brakes
If you tow more than 1,000 lbs (450 kg), use trailer
brakes. Because your vehicle has anti-lock brakes,
don’t try to tap into your vehicle’s hydraulic brake
system. If you do, both brake systems won’t
work well, or at all.
Be sure to read and follow the instructions for the
trailer brakes so you’ll be able to install, adjust
and maintain them properly.
Driving with a Trailer
Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
you’ll want to get to know your rig. Acquaint
yourself 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 a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving
and then apply the trailer brake controller by hand
to be sure the brakes are working. This lets you
check your electrical connection at the same time.
During your 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 your vehicle without
a trailer. This can help you avoid situations
that require heavy braking and sudden turns.
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Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a
good deal longer, you’ll need to go much farther
beyond the passed vehicle before you can
return to your lane.
Backing Up
Hold the bottom of the steering wheel with
one hand. Then, to move the trailer to the left,
just 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. Your vehicle could
be damaged. Avoid making very sharp turns
while trailering.When you’re turning with a trailer, make wider
turns than normal. Do this so your 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
When you tow a trailer, your vehicle may need a
different turn signal asher and/or extra wiring.
Check with your dealer/retailer. The arrows
on your instrument panel will ash whenever you
signal a turn or lane change. Properly hooked
up, the trailer lamps will also ash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the
bulbs on the trailer are burned out. Thus, you may
think drivers behind you are seeing your signal
when they are not. It’s important to check
occasionally to be sure the trailer bulbs are
still working.
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Driving on Grades
Your vehicle is designed primarily as a passenger
and load carrying vehicle. If you tow a trailer,
your vehicle will require more frequent
maintenance due to the additional load. Because
of the added load of the trailer, your 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.
Reduce speed and shift to a lower gear before
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.
On a long uphill grade, shift down and reduce
your speed to around 55 mph (88 km/h) to reduce
the possibility of the engine and the transmission
overheating.
Parking on Hills
{CAUTION:
You really should not park your vehicle,
with a trailer attached, on a hill.
If something goes wrong, your rig could
start to move. People can be injured, and
both your vehicle and the trailer can be
damaged.
But if you ever have to park your rig on a hill,
here’s how to do it:
1. Apply your regular brakes, but don’t shift
into PARK (P).
When parking uphill, turn your wheels away
from the curb. When parking downhill,
turn your wheels into the curb.
2. Have someone place chocks behind the
trailer wheels.
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3. When the chocks are in place, release the
regular brakes until the chocks absorb
the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal
down while you:
start your 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
Your vehicle will need service more often
when you’re pulling a trailer. SeeScheduled
Maintenance on page 502for more information.
Things that are especially important in trailer
operation are automatic transmission uid
(don’t overll), engine oil, axle lubricant, drive
belt, cooling system and brake system. Each of
these is covered in this manual, and the Index will
help you nd them quickly. If you’re trailering,
it’s a good idea to review this information before
you start your trip.
Check periodically to see that all hitch nuts and
bolts are tight.
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Trailer Wiring Harness
Your vehicle is equipped with the following wiring
harness for towing a trailer.
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
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed*
Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in
the underhood electrical center, but the wires
are not connected. They should be connected by
your dealer/retailer or a qualied service center.
If you are charging a remote (non-vehicle) battery,
press the tow/haul mode button located at the
end of the shift lever. This will boost the vehicle
system voltage and properly charge the battery.
If the trailer is too light for tow/haul mode, you can
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
Your cooling system may temporarily overheat
during severe operating conditions. SeeEngine
Overheating on page 410.
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Gasoline Octane
Use regular unleaded gasoline with a posted
octane rating of 87 or higher. For best performance
or trailer towing, you could choose to use middle
grade 89 octane unleaded gasoline. If the
octane rating is less than 87, you might notice
an audible knocking noise when you drive,
commonly referred to as spark knock. If this
occurs, use a gasoline rated at 87 octane or higher
as soon as possible. If you are using gasoline
rated at 87 octane or higher and you hear heavy
knocking, the engine needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 or 3.511 in Canada. Some
gasolines contain an octane-enhancing additive
called methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend against the
use of gasolines containing MMT. SeeAdditives
on page 389for additional information.
California Fuel
If your vehicle is certied to meet California
Emissions Standards, it is designed to operate
on fuels that meet California specications.
See the underhood emission control label.
If this fuel is not available in states adopting
California emissions standards, your vehicle will
operate satisfactorily on fuels meeting federal
specications, but emission control system
performance might be affected. The malfunction
indicator lamp could turn on and your vehicle might
fail a smog-check test. SeeMalfunction Indicator
Lamp on page 226. If this occurs, return to
your authorized dealer/retailer for diagnosis.
If it is determined that the condition is caused
by the type of fuel used, repairs might not
be covered by your warranty.
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Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
A good time to check the automatic transmission
uid level is when the engine oil is changed.
Change the uid at the intervals listed inAdditional
Required Services on page 504, and be sure to
use the transmission uid listed inRecommended
Fluids and Lubricants on page 511.
How to Check Automatic Transmission
Fluid
Because this operation can be a little difficult, you
may choose to have this done at the dealer/retailer
service department.
If you do it yourself, be sure to follow all the
instructions here, or you could get a false reading
on the dipstick.Notice:Too much or too little uid can
damage your transmission. Too much can
mean that some of the uid could come out
and fall on hot engine parts or exhaust system
parts, starting a re. Too little uid could
cause the transmission to overheat. Be sure to
get an accurate reading if you check your
transmission uid.
Wait at least 30 minutes before checking the
transmission uid level if you have been driving:
When outside temperatures are above
90°F (32°C).
At high speed for quite a while.
In heavy traffic — especially in hot weather.
While pulling a trailer.
To get the right reading, the uid should be at
normal operating temperature, which is 180°F to
200°F (82°C to 93°C).
Get the vehicle warmed up by driving about
15 miles (24 km) when outside temperatures are
above 50°F (10°C). If it is colder than 50°F (10°C),
you may have to drive longer.
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CAUTION: (Continued)
If you keep driving when the vehicles
engine is overheated, the liquids in it can
catch re. You or others could be badly
burned. Stop your engine if it overheats,
and get out of the vehicle until the engine
is cool.
SeeOverheated Engine Protection
Operating Mode on page 412for
information on driving to a safe place in
an emergency.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not
be covered by your warranty. SeeOverheated
Engine Protection Operating Mode on page 412
for information on driving to a safe place in an
emergency.
If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or
hear no steam, the problem may not be too
serious. Sometimes the engine can get a little
too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of
steam, try this for a minute or so:
1. If your air conditioner is on, turn it off.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
3. If you are in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving — DRIVE (D) or LOW (L).
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