trailer GMC ENVOY DENALI 2009 User Guide

Steps for Determining Correct Load Limit
1.Locate the statement “The combined weight
of occupants and cargo should never exceed
XXX kg or XXX lbs” on your vehicle’s placard.
2.Determine the combined weight of the driver
and passengers that will be riding in your
vehicle.
3.Subtract the combined weight of the driver
and passengers from XXX kg or XXX lbs.
4.The resulting gure equals the available
amount of cargo and luggage load capacity.
For example, if the “XXX” amount equals
1400 lbs and there will be ve 150 lb
passengers in your vehicle, the amount of
available cargo and luggage load capacity is
650 lbs (1400−750 (5 x 150) = 650 lbs).
5.Determine the combined weight of luggage
and cargo being loaded on the vehicle. That
weight may not safely exceed the available
cargo and luggage load capacity calculated
in Step 4.
6.If your vehicle will be towing a trailer, the load
from your trailer will be transferred to your
vehicle. Consult this manual to determine how
this reduces the available cargo and luggage
load capacity of your vehicle. SeeTowing
a Trailer on page 4-46for important
information on towing a trailer, towing safety
rules and trailering tips.
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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 weights. Please note your
vehicle’s Certication/Tire label or consult
your dealer for additional details.
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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
To avoid damage, the disabled vehicle should be towed
with all four wheels off the ground. Consult your
dealer/retailer or a professional towing service if the
disabled vehicle must be towed. SeeRoadside
Assistance Program on page 7-7.
To tow the 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 the vehicle
behind another vehicle – such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as dinghy towing and dolly towing.
Dinghy towing is towing the vehicle with all four wheels on
the ground. Dolly towing is towing the vehicle with two
wheels on the ground and two wheels up on a device
known as a dolly.
Here are some important things to consider before
recreational vehicle towing:
What is the towing capacity of the towing vehicle?
Be sure to read the tow vehicle manufacturer’s
recommendations.
What is the distance that will be travelled? Some
vehicles have restrictions on how far and how
long they can tow.
Is the proper towing equipment going to be used?
See your dealer/retailer or trailering professional
for additional advice and equipment
recommendations.
Is the vehicle ready to be towed? Just as preparing
the vehicle for a long trip, make sure the vehicle is
prepared to be towed. SeeBefore Leaving on a
Long Trip on page 4-26.
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Dinghy Towing
Two-Wheel-Drive Vehicles
Notice:If the vehicle is towed with all four wheels
on the ground, the drivetrain components could
be damaged. The repairs would not be covered by
the vehicle warranty. Do not tow the 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 atbed truck or trailer.
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Towing a Trailer
{CAUTION:
The driver can lose control when pulling a trailer if
the correct equipment is not used or the vehicle is
not driven properly. For example, if the trailer is
too heavy, the brakes may not work well — or
even at all. The driver and passengers could be
seriously injured. The vehicle may also be
damaged; the resulting repairs would not be
covered by the vehicle warranty. Pull a trailer only
if all the steps in this section have been followed.
Ask your dealer/retailer for advice and information
about towing a trailer with the vehicle.Notice:Pulling a trailer improperly can damage the
vehicle and result in costly repairs not covered
by the vehicle warranty. To pull a trailer correctly,
follow the advice in this section and see your
dealer/retailer for important information about
towing a trailer with the vehicle.
To identify the trailering capacity of the vehicle, read
the information in “Weight of the Trailer” that appears
later in this section.
Trailering is different than just driving the vehicle by itself.
Trailering means changes in handling, acceleration,
braking, durability and fuel economy. Successful, safe
trailering takes correct equipment, and it has to be used
properly.
The following information has 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 pulling a
trailer.
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Pulling A Trailer
Here are some important points:
There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
the rig will be legal, not only where you live but
also where you will 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.
Do not tow a trailer at all during the rst 500 miles
(800 km) the new vehicle is driven. The engine,
axle or other parts could be damaged.
Then, during the rst 500 miles (800 km) that a
trailer is towed, do not drive over 50 mph (80 km/h)
and do not make starts at full throttle. This helps
the engine and other parts of the vehicle wear in at
the heavier loads.
Vehicles with an automatic transmissions can tow
in D (Drive). Shift the transmission to a lower gear
if the transmission shifts too often 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
The weight on the vehicle’s tires
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how the rig is used. For example, speed,
altitude, road grades, outside temperature and how much
the vehicle is used to pull a trailer are all important. It can
depend on any special equipment on the vehicle, and the
amount of tongue weight the vehicle can carry. 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.
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Look in the following chart to nd the maximum trailer weight for the vehicle.
Vehicle Axle Ratio Max. Trailer Wt. *GCWR
2WD Envoy (4.2 L 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)
2WD Envoy (5.3 L V8 Engine)3.42 6,100 lbs (2 767 kg) 11,000 lbs (4 990 kg)
3.73 6,600 lbs (2 994 kg) 11,500 lbs (5 216 kg)
4WD Envoy (4.2 L L6 Engine)3.42 5,200 lbs (2 359 kg) 10,000 lbs (4 536 kg)
3.73 5,700 lbs (2 858 kg) 10,500 lbs (4 763 kg)
4.10 6,200 lbs (2 812 kg) 11,000 lbs (4 990 kg)
4WD Envoy (5.3 L V8 Engine)3.42 6,000 lbs (2 721 kg) 11,000 lbs (4 990 kg)
3.73 6,500 lbs (2 948 kg) 11,500 lbs (5 216 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 the vehicle should not be
exceeded.
Ask your dealer for our trailering information or advice, or write us at our Customer Assistance Offices. SeeCustomer
Assistance Offices on page 7-6for more information.
4-48

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
Loading the Vehicle on page 4-31for more information
about the vehicle’s maximum load capacity.The trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight, up to a
maximum or 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, up to a
maximum of 900 lbs (408 kg) with a weight distributing
hitch.
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Do not exceed the maximum allowable tongue weight
for the 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 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 the GVWR (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.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:
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 is 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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If the vehicle has many options and there is a front seat
passenger and two rear seat passengers with some
luggage and gear in the vehicle as well. 300 lbs (136 kg)
could be added to the front axle weight and 400 lbs
(181 kg) to the rear axle weight. The vehicle now weighs:
Weight is still below 7,200 lbs (3 266 kg) and you
might think 700 additional pounds (318 kg) should be
subtracted from the trailering capacity to stay within
GCWR limits. The maximum trailer would only be
7,800 lbs (3 538 kg). You may go further and think the
tongue weight should be limited to less than 1,000 lbs
(454 kg) to avoid exceeding GVWR. But the effect on the
rear axle must still be considered. Because the rear axle
now weighs 3,100 lbs (1 406 kg), 900 lbs (408 kg) can be
put 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 only
600 lbs (272 kg) of tongue weight that can be handled.Since tongue weight is usually at least 10 percent of total
loaded trailer weight, expect that the largest trailer the
vehicle can properly handle is 6,000 lbs (2 721 kg).
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
Be sure the vehicle’s tires are inated to the upper limit
for cold tires. These numbers can be found on the
Certication/Tire Label located on the B-pillar below the
door latch or seeLoading the Vehicle on page 4-31
for more information. Make sure not to go over the GVW
limit for the vehicle, or the GAWR, including the weight
of the trailer tongue. If using a weight distributing
hitch, make sure not to go over the rear axle limit before
applying the weight distribution spring bars.
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.
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