2007 GMC ENVOY DENALI towing

{CAUTION:
If your vehicle has four-wheel drive, it will
be free to roll — even if the shift lever is
in PARK (P) — if the transfer case is in
NEUTRAL. So be sure the transfer case is
in a drive gear — not in NEUTRAL. See
Four-Wheel Drive on page 122.
Follow the proper steps to be sure your vehicle
will not move. SeeShifting Into Park (P) on
page 127.
If you are pulling a trailer, seeTowing a Trailer on
page 362.
Mirrors
Manual Rearview Mirror
Your vehicle may have this feature. While sitting in
a comfortable driving position, adjust the rearview
mirror so you can see clearly behind your
vehicle. Grip the mirror in the center to move it up
or down and side to side. The day/night control,
located at the bottom of the mirror, adjusts
the mirror to reduce headlamp glare from behind
during evening or dark conditions. Turn the
control clockwise for night use; return it to the
center for daytime use.
Manual Rearview Mirror with
OnStar
®
Your vehicle may have a rearview mirror with the
OnStar®system.
Control buttons for the OnStar
®system are at the
bottom of the mirror. See your dealer for more
information on the OnStar
®system and how
to subscribe to OnStar®. Also, seeOnStar®
System on page 145for more information about
the services OnStar®provides.
133

Turn and Lane-Change Signals
The turn signal has two upward (for right) and
two downward (for left) positions. These positions
let you signal a turn or a lane change.
To signal a turn, move the lever all the way up or
down. When the turn is nished, the lever
returns automatically.
An arrow on the
instrument panel cluster
ashes in the direction
of the turn or lane
change.
To signal a lane change, raise or lower the lever
until the arrow starts to ash. Hold it there until you
complete your lane change. The lever returns
by itself when released. The bottom of the outside
rearview mirrors might also have lane change
indicators.As you signal a turn or a lane change, if the
arrows ash more quickly than normal, a signal
bulb could be burned out and other drivers will not
see your turn signal.
If a bulb is burned out, replace it to help avoid an
accident. If the arrows do not go on at all when
you signal a turn, check the fuse. SeeFuses and
Circuit Breakers on page 493and check for
burned-out bulbs.
If you have a trailer towing option with added
wiring for the trailer lamps, a turn signal asher is
used. With this asher installed, the signal
indicator ashes even if a turn signal bulb is
burned out. Check the front and rear turn signal
lamps regularly to make sure they are working.
Turn Signal On Chime
If your turn signal is left on for more than 3/4 of a
mile (1.2 km), a chime sounds at each ash of
the turn signal. To turn off the chime, move
the turn signal lever to the off position.
172

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
206

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.
211

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.
350

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