towing GMC ENVOY DENALI 2007 User Guide

Readings in the low warning zone may occur
when a large number of electrical accessories are
operating in the vehicle and the engine is left
idling for an extended period. This condition
is normal since the charging system is not able to
provide full power at engine idle. As engine
speeds are increased, this condition should correct
itself as higher engine speeds allow the charging
system to create maximum power.
You can only drive for a short time with the
reading in either warning zone. If you must drive,
turn off all unnecessary accessories.
Readings in either warning zone indicate a
possible problem in the electrical system. Have
the vehicle serviced as soon as possible.
Brake System Warning Light
When the ignition is on, the brake system warning
light will come on when you set your parking
brake. The light will stay on if your parking brake
does not release fully. If it stays on after your
parking brake is fully released, it means your
vehicle has a brake problem. A chime may also
sound when the light comes on.Your vehicle’s hydraulic brake system is divided
into two parts. If one part is not working, the other
part can still work and stop you. For good
braking, though, you need both parts working well.
If the warning light comes on, there could be a
brake problem. Have your brake system inspected
right away.
This light should come on briey when you turn
the ignition key to RUN. If it does not come
on then, have it xed so it will be ready to warn
you if there is a problem.
If the light comes on while you are driving, pull off
the road and stop carefully. You may notice that the
pedal is harder to push or the pedal may go closer
to the oor. It may take longer to stop. If the light is
still on, have the vehicle towed for service. See
Towing Your Vehicle on page 354.
United StatesCanada
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This light should come on, as a check to show
you it is working, when the ignition is on and the
engine is not running. If the light does not
come on, have it repaired. This light will also
come on during a malfunction in one of two ways:
Light Flashing— A misre condition has
been detected. A misre increases vehicle
emissions and may damage the emission
control system on your vehicle. Diagnosis and
service may be required.
Light On Steady— An emission control
system malfunction has been detected on
your vehicle. Diagnosis and service may
be required.
If the Light is Flashing
The following may prevent more serious damage
to your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possibleIf the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do
so, stop the vehicle. Find a safe place to park
your vehicle. Turn the key off, wait at least
10 seconds and restart the engine. If the light
remains on steady, see “If the Light Is On Steady”
following. If the light is still ashing, follow the
previous steps, and see your dealer for service as
soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully
install the cap. SeeFilling the Tank on page 385.
The diagnostic system can determine if the
fuel cap has been left off or improperly installed.
A loose or missing fuel cap will allow fuel to
evaporate into the atmosphere. A few driving trips
with the cap properly installed should turn the
light off.
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Your Driving, the Road, and
Your Vehicle............................................ 302
Defensive Driving...................................... 302
Drunken Driving........................................ 303
Control of a Vehicle.................................. 306
Braking...................................................... 306
Anti-Lock Brake System (ABS).................. 307
Braking in Emergencies............................. 309
Locking Rear Axle..................................... 309
StabiliTrak
®System................................... 309
Steering.................................................... 314
Off-Road Recovery.................................... 316
Passing..................................................... 316
Loss of Control.......................................... 318
Off-Road Driving........................................ 319
Driving at Night......................................... 334
Driving in Rain and on Wet Roads............ 335
City Driving............................................... 338Freeway Driving........................................ 339
Before Leaving on a Long Trip.................. 340
Highway Hypnosis..................................... 341
Hill and Mountain Roads........................... 342
Winter Driving........................................... 344
If Your Vehicle is Stuck in Sand, Mud,
Ice, or Snow.......................................... 348
Rocking Your Vehicle to Get It Out........... 348
Loading Your Vehicle................................ 349
Adding a Snow Plow or Similar
Equipment.............................................. 354
Towing........................................................ 354
Towing Your Vehicle ................................. 354
Recreational Vehicle Towing...................... 355
Electronically Controlled Air Suspension
System.................................................. 360
Towing a Trailer........................................ 362
Section 4 Driving Your Vehicle
301

If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
In order to free your vehicle when it is stuck,
you will need to spin the wheels, but you do not
want to spin your wheels too fast. The method
known as rocking can help you get out when you
are stuck, but you must use caution.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or others
could be injured. And, the transmission or
other parts of the vehicle can overheat.
That could cause an engine compartment
re or other damage. When you are stuck,
spin the wheels as little as possible. Do not
spin the wheels above 35 mph (55 km/h) as
shown on the speedometer.Notice:Spinning the wheels can destroy
parts of your vehicle as well as the tires. If you
spin the wheels too fast while shifting the
transmission back and forth, you can destroy
the transmission.
For information about using tire chains on your
vehicle, seeTire Chains on page 461.
Rocking Your Vehicle to Get It Out
First, turn the steering wheel left and right. That will
clear the area around the front wheels. If you have
a four-wheel-drive vehicle, shift into Four-Wheel
High. Then shift back and forth between
REVERSE (R) and a forward gear, spinning the
wheels as little as possible. Release the accelerator
pedal while you shift, and press lightly on the
accelerator pedal when the transmission is in gear.
By slowly spinning the wheels in the forward and
reverse directions, you will cause a rocking motion
that may free your vehicle. If that does not get your
vehicle out after a few tries, it may need to be towed
out. If your vehicle does need to be towed out, see
Towing Your Vehicle on page 354.
348

The Tire and Loading Information label also shows
the size of the original equipment tires (C) and
the recommended cold tire ination pressures (D).
For more information on tires and ination see
Tires on page 439andInation - Tire Pressure on
page 447.
There is also important loading information on the
vehicle Certication/Tire label. It tells you the
Gross Vehicle Weight Rating (GVWR) and
the Gross Axle Weight Rating (GAWR) for the
front and rear axle. See “Certication/Tire Label”
later in this section.
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 362for important information
on towing a trailer, towing safety rules and
trailering tips.
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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.
354

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.
357

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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