tow GMC ENVOY 2007 Service Manual

If you put things inside your vehicle — like
suitcases, tools, packages, or anything
else — they will go as fast as the vehicle goes.
If you have to stop or turn quickly, or if there is a
crash, they will keep going.
{CAUTION:
Things you put inside your vehicle can
strike and injure people in a sudden stop
or turn, or in a crash.
Put things in the cargo area of your
vehicle. Try to spread the weight
evenly.
Never stack heavier things, like
suitcases, inside the vehicle so that
some of them are above the tops of
the seats.
Do not leave an unsecured child
restraint in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down
unless you need to.There is also important loading information for
off-road driving in this manual. See “Loading Your
Vehicle for Off-Road Driving” underOff-Road
Driving on page 319.
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. SeeRoadside Assistance Program on
page 532.
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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.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 340.
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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.
Four-Wheel-Drive Vehicles
Four-wheel-drive vehicles can be dinghy towed if
you follow the proper procedures. The transmission
has no provisions for internal lubrication while being
towed, so it is important that you follow all the
steps listed in this manual to dinghy tow your
four-wheel-drive vehicle.
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Use the following procedure to tow your vehicle:
1. Shift the transmission to PARK (P).
2. Turn the engine off, but leave the ignition on.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the
tow vehicle.
{CAUTION:
Shifting a four-wheel-drive vehicle’s
transfer case into NEUTRAL can cause
your vehicle to roll even if the transmission
is in PARK (P). You or others could be
injured. Make sure the parking brake is
rmly set before you shift the transfer case
to NEUTRAL.5. Shift the transfer case to NEUTRAL (N).
SeeFour-Wheel Drive on page 122for
the proper procedure to select the
NEUTRAL (N) position for your vehicle.
6. Release the parking brake only after the
vehicle being towed is rmly attached to
the towing vehicle.
7. Turn the ignition off.
After towing, see “Shifting Out of Neutral” under
Four-Wheel Drive on page 122.
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Dolly Towing
Front Towing
(Front Wheels Off the Ground)
Two-Wheel-Drive Vehicles
Notice:If you tow a two-wheel-drive vehicle
with the rear wheels on the ground, the
transmission could be damaged. The repairs
would not be covered by your warranty.
Never tow your vehicle with the rear wheels on
the ground.
Four-Wheel-Drive Vehicles
Four-wheel-drive vehicles can be dolly towed with
the rear wheels on the ground.
Use the following procedure to tow your vehicle:
1. Drive the vehicle onto the tow dolly.
2. Shift the automatic transmission to PARK (P).
3. Turn the engine off, but leave the ignition on.
4. Firmly set the parking brake.
5. Securely attach the vehicle being towed to
the dolly.
{CAUTION:
Shifting a four-wheel-drive vehicle’s
transfer case into NEUTRAL can cause
your vehicle to roll even if the transmission
is in PARK (P). You or others could be
injured. Make sure the parking brake is
rmly set before you shift the transfer case
to NEUTRAL.
6. Shift the transfer case to NEUTRAL (N).
SeeFour-Wheel Drive on page 122for
the proper procedure to select the
NEUTRAL (N) position for your vehicle.
7. Release the parking brake only after the
vehicle being towed is rmly attached to
the towing vehicle.
8. Turn the ignition off.
After towing, see “Shifting Out of Neutral”
underFour-Wheel Drive on page 122.
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Rear Towing
(Rear Wheels Off the Ground)
(Two-Wheel or Four-Wheel-Drive Vehicles)
Use the following procedure to tow your vehicle
from the rear:
1. Drive the vehicle onto the dolly.
2. Firmly set the parking brake. SeeParking
Brake on page 126for more information.
3. Shift the transmission in PARK (P).4. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the
tow vehicle. Use an adequate clamping device
to ensure that the front wheels are locked
into the straight position.
5. Release the parking brake only after the
vehicle being towed is rmly attached to
the towing vehicle.
6. Turn the ignition to LOCK.
If the tow vehicle will not be started or driven
for six weeks or more, remove the battery
cable from the negative terminal (post) of the
battery.
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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.
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. It can also depend
on any special equipment that you have on your
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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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
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. See Loading Your
Vehicle for more information about your vehicle’s
maximum load capacity.
The trailer tongue weight (A) should be 10 percent
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.
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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 or see Loading Your Vehicle for 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 (A) 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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