2007 GMC CANYON Owner's Manual

After you’ve loaded your trailer, weigh the trailer
and then the tongue, separately, to see if the
weights are proper. If they aren’t you may be able
to get them right simply by moving some of the
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 the GVWR (Gross
Vehicle Weight Rating) or the RGAWR (Rear
Gross Axle Weight Rating). 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).
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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). 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.
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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 located at the bottom of the
center pillar on the driver’s side of the vehicle, or
seeLoading Your Vehicle on page 286. Then be
sure you don’t go over the GVWR 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.
Weight-Distributing Hitches and Weight
Carrying Hitches
You can use your step bumper hitch for trailers up to
2,000 lbs (907 kg) total weight, and 200 lbs (90 kg)
tongue weight.
Notice:If you use a step-bumper hitch, your
bumper could be damaged in sharp turns.
Make sure you have ample room when turning
to avoid contact between the trailer and the
bumper.
Safety Chains
You should always attach chains between your
vehicle and your 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.
For trailers up to 2,000 lbs (907 kg) you may attach
the safety chains to the attaching points on the
bumper. For heavier trailers, follow the trailer
or hitch manufacturer’s recommendation for
attaching safety chains. Always leave just enough
slack so you can turn with your rig. Never allow
safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 lbs (450 kg)
loaded, then it needs its own brakes — and
they must be adequate. Be sure to read and follow
the instructions for the trailer brakes so you’ll be
able to install, adjust and maintain them properly.
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Your trailer’s brake system can tap into the
vehicle’s hydraulic brake system only if:
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of uid from your
vehicle’s master cylinder. Otherwise,
both braking systems won’t work well. You
could even lose your brakes.
If everything checks out this far, then make the
brake uid tap at the port on the master cylinder
that sends uid to the rear brakes. But don’t
use copper tubing for this. If you do, it will bend
and nally break off. Use steel brake tubing.
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.
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.
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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 has to have
extra wiring and a heavy-duty turn signal asher.
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.
Driving On Grades
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.
When towing at high altitude on steep uphill
grades, consider the following: Engine coolant
will boil at a lower temperature than at normal
altitudes. If you turn your engine off immediately
after towing at high altitude on steep uphill grades,
your vehicle may show signs similar to engine
overheating. To avoid this, let the engine run while
parked (preferably on level ground) with the
automatic transmission in PARK (P) (or the manual
transmission out of gear and the parking brake
applied) for a few minutes before turning the
engine off. If you do get the overheat warning,
seeEngine Overheating on page 340.
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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) yet, or into gear for a manual
transmission. When parking uphill, turn your
wheels away from the curb. When parking
downhill, turn your wheels into the curb.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel 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 then shift into PARK (P),
or REVERSE (R) for a manual transmission.
SeeParking Brake on page 130for more
information.
5. If you have a four-wheel-drive vehicle, be sure
the transfer case is in a drive gear and not in
NEUTRAL. SeeFour-Wheel Drive on page 126
for more information.
6. 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.
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Maintenance When Trailer Towing
Your vehicle will need service more often
when you’re pulling a trailer. SeeScheduled
Maintenance on page 437for more on this. Things
that are especially important in trailer operation
are automatic transmission uid (don’t overll),
engine oil, axle lubricant, 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 these sections before you start your trip.
Check periodically to see that all hitch nuts and
bolts are tight.
Trailer Wiring Harness
Your vehicle may be equipped with a four-pin
trailer towing harness. This harness has a four-pin
trailer connector that is attached to a bracket on
the hitch platform. The four-wire harness contains
the following trailer circuits:
Yellow: Left Stop/Turn Signal
Green: Right Stop/Turn Signal
Brown: Taillamps/Park lamps
White: Ground
Trailer Recommendations
You must subtract your hitch load from the
CWR for your vehicle. Weigh your vehicle with
your trailer attached, so that you won’t go over
the GVWR or the GAWR.
You’ll get the best performance if you spread out
the weight of your load the right way, and if
you choose the correct hitch and trailer brakes.
For more information, seeTowing a Trailer
on page 300later in this section.
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✍NOTES
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