trailer GMC ENVOY DENALI 2005 User Guide

Certication/Tire Label
A vehicle specic Certication/Tire label is found on the
rear edge of the driver’s door. The label shows the
size of your vehicle’s original tires and the ination
pressures needed to obtain the gross weight capacity of
your vehicle. This is called Gross Vehicle Weight
Rating (GVWR). The GVWR includes the weight of the
vehicle, all occupants, fuel, cargo and trailer tongue
weight, if pulling a trailer.The Certication/Tire label also tells you the maximum
weights for the front and rear axles, called Gross
Axle Weight Rating (GAWR). To nd out the actual loads
on your front and rear axles, you need to go to a
weigh station and weigh your vehicle. Your dealer can
help you with this. Be sure to spread out your load
equally on both sides of the centerline.
Never exceed the GVWR for your vehicle, or the GAWR
for either the front or rear axle.
And, if you do have a heavy load, you should spread
it out.
Similar appearing vehicles may have different GVWRs
and capacity weight. Please note your vehicle’s
Certication/Tire label or consult your dealer for
additional details.
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Indicator Light
The indicator light on the inator switch in the rear
passenger compartment also serves as an indicator for
internal system error. If the indicator light is ashing
without the load leveling function or the inator being
active, turn off the ignition. The next day turn on
the ignition and check the indicator light. The vehicle
can be driven with the light ashing, but if it is you
should have the vehicle serviced as soon as possible.
Adding a Snow Plow or Similar
Equipment
Your vehicle was neither designed nor intended for a
snow plow.
Notice:Adding a snow plow or similar equipment
to your vehicle can damage it, and the repairs would
not be covered by warranty. Do not install a snow
plow or similar equipment on your vehicle.
Towing
Towing Your Vehicle
Consult your dealer or a professional towing service if
you need to have your disabled vehicle towed. See
Roadside Assistance Program on page 7-6.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see “Recreational Vehicle Towing” following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle – such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as “dinghy towing” (towing your vehicle
with all four wheels on the ground) and “dolly towing”
(towing your vehicle with two wheels on the ground and
two wheels up on a device known as a “dolly”).
With the proper preparation and equipment, many
vehicles can be towed in these ways. See “Dinghy
Towing” and “Dolly Towing,” following. You may
also need brakes for the vehicle being towed. See your
dealer for additional trailering information.
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Here are some important things to consider before you
do recreational vehicle towing:
What’s the trailering capacity of the towing vehicle?
Be sure you read the tow vehicle manufacturer’s
recommendations.
How far will you tow? Some vehicles have
restrictions on how far and how long they
can be towed.
Do you have the proper towing equipment? See
your dealer or trailering professional for additional
advice and equipment recommendations.
Is your vehicle ready to be towed? Just as you
would prepare your vehicle for a long trip, you’ll
want to make sure your vehicle is prepared to be
towed. SeeBefore Leaving on a Long Trip on
page 4-36.
Dinghy Towing
Two-Wheel-Drive Vehicles
Notice:If you tow your vehicle with all four wheels
on the ground, the drivetrain components could
be damaged. The repairs would not be covered by
your warranty. Do not tow your vehicle with all
four wheels on the ground.
Two-wheel-drive vehicles should not be towed with all
four wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed. To properly tow these vehicles,
they should be placed on a platform trailer.
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Towing a Trailer
{CAUTION:
If you do not use the correct equipment and
drive properly, you can lose control when you
pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well — or even
at all. You and your passengers could be
seriously injured. Pull a trailer only if you have
followed all the steps in this section. Ask your
dealer for advice and information about towing
a trailer with your vehicle.
Notice:Pulling a trailer improperly can damage
your vehicle and result in costly repairs that would
not be covered by your warranty. Always follow
the instructions in this section and check with your
dealer for more information about towing a trailer
with your vehicle.To identify the trailering capacity of your vehicle, you
should read the information in “Weight of the Trailer” that
appears later in this section.
Trailering is different than just driving your vehicle by
itself. Trailering means changes in acceleration, braking,
handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and it has to be
used properly.
That’s the reason for this part. In it are many time-tested,
important trailering tips and safety rules. Many of
these are important for your safety and that of your
passengers. So please read this section carefully before
you pull a trailer.
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If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live
but also where you’ll be driving. A good source for
this information can be state or provincial police.
Consider using a sway control. See “Hitches” later
in this section.
Don’t tow a trailer at all during the rst 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the rst 500 miles (800 km) that you
tow a trailer, don’t drive over 50 mph (80 km/h)
and don’t make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at
the heavier loads.
You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary, a
lower gear selection if the transmission shifts
too often (e.g., under heavy loads and/or hilly
conditions).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
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Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For example, speed, altitude, road grades, outside temperature and how
much your vehicle is used to pull a trailer are all important. And, it can also depend on any special equipment that
you have on your vehicle.
Look in the following chart to nd the maximum trailer weight for your vehicle.
Vehicle Axle Ratio Max.Trailer Wt. *GCWR
2WD Envoy (L6 Engine)3.42 5,300 lbs (2 404 kg) 10,000 lbs (4 536 kg)
3.73 5,800 lbs (2 631 kg) 10,500 lbs (4 763 kg)
4.10 6,300 lbs (2 858 kg) 11,000 lbs (4 990 kg)
4WD Envoy (L6 Engine)3.42 5,100 lbs (2 313 kg) 10,000 lbs (4 536 kg)
3.73 5,600 lbs (2 540 kg) 10,500 lbs (4 763 kg)
4.10 6,100 lbs (2 767 kg) 11,000 lbs (4 990 kg)
2WD Envoy XL (L6 Engine)3.42 5,000 lbs (2 268 kg) 10,000 lbs (4 536 kg)
3.73 5,500 lbs (2 495 kg) 10,500 lbs (4 763 kg)
4.10 6,000 lbs (2 722 kg) 11,000 lbs (4 990 kg)
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Vehicle Axle Ratio Max.Trailer Wt. *GCWR
4WD Envoy XL (L6 Engine)3.42 4,800 lbs (2 177 kg) 10,000 lbs (4 536 kg)
3.73 5,300 lbs (2 404 kg) 10,500 lbs (4 763 kg)
4.10 5,800 lbs (2 631 kg) 11,000 lbs (4 990 kg)
2WD Envoy XL (V8 Engine)3.42 5,900 lbs (2 676 kg) 11,000 lbs (4 990 kg)
3.73 7,000 lbs (3 175 kg) 12,500 lbs (5 670 kg)
4WD Envoy XL (V8 Engine)3.42 5,700 lbs (2 585 kg) 11,000 lbs (4 990 kg)
3.73 6,500 lbs (2 948 kg) 12,500 lbs (5 670 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 conversion. The GCWR for your vehicle should
not be exceeded.
You can ask your dealer for our trailering information
or advice, or you can write us at the address listed
in your Warranty and Owner Assistance Information
Booklet.In Canada, write to:
General Motors of Canada Limited
Customer Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
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Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total or gross weight of
your vehicle. The Gross Vehicle Weight (GVW) includes
the curb weight of the vehicle, any cargo you may carry in
it, and the people who will be riding in the vehicle. If you
have a lot of options, equipment, passengers or cargo in
your vehicle, it will reduce the tongue weight your vehicle
can carry, which will also reduce the trailer weight your
vehicle can tow. And if you will tow a trailer, you must add
the tongue load to the GVW because your vehicle will be
carrying that weight, too. SeeLoading Your Vehicle on
page 4-44for more information about your vehicle’s
maximum load capacity.The trailer tongue weight (A) should be 10 to 15 percent
of the total loaded trailer weight (B), up to a maximum of
400 lbs (181 kg) with a weight carrying hitch. The trailer
tongue weight (A) should be 10 percent to 15 percent of
the total loaded trailer weight (A), up to a maximum of
900 lbs (408 kg) for a weight distributing hitch.
Do not exceed the maximum allowable tongue weight
for your vehicle. Choose the shortest hitch extension
that will position the hitch ball closest to the vehicle. This
will help reduce the effect of trailer tongue weight on
the rear axle.
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 items around in the 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 label at the rear edge of the driver’s door.
SeeLoading Your Vehicle on page 4-44for more
information. Then, be sure you don’t go over the GVW
limit for your vehicle, or the GAWR, including the
weight of the trailer tongue. If you use a weight
distributing hitch, make sure you don’t go over the rear
axle limit before you apply the weight distribution
spring bars.
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
When using a weight-distributing hitch, the hitch must
be adjusted so the distance remains the same both
before and after coupling the trailer to the tow vehicle.
If you use a step-bumper hitch, the bumper could
be damaged in sharp turns. Make sure there is ample
room when turning to avoid contact between the
trailer and the bumper.(A) Body to Ground Distance, (B) Front of Vehicle
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If you will be pulling a trailer that, when loaded, will
weigh more than 4,000 lbs (1 814 kg) be sure to use a
properly mounted weight-distributing hitch and sway
control of the proper size. This equipment is very
important for proper vehicle loading and good handling
when driving. Always use a sway control if the trailer
will weigh more than these limits. You can ask a
hitch dealer about sway controls.
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. 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.
Never allow safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,500 lbs (680 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.
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.
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