GMC ENVOY DENALI 2007 Owners Manual

During your trip, check occasionally to be sure
that the load is secure, and that the lamps and any
trailer brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead
as you would when driving your vehicle without
a trailer. This can help you avoid situations
that require heavy braking and sudden turns.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a
good deal longer, you’ll need to go much farther
beyond the passed vehicle before you can
return to your lane.
Backing Up
Hold the bottom of the steering wheel with
one hand. Then, to move the trailer to the left, just
move that hand to the left. To move the trailer
to the right, move your hand to the right. Always
back up slowly and, if possible, have someone
guide you.
Making Turns
Notice:Making very sharp turns while
trailering could cause the trailer to come in
contact with the vehicle. Your vehicle could be
damaged. Avoid making very sharp turns
while trailering.
When you’re turning with a trailer, make wider
turns than normal. Do this so your trailer
won’t strike soft shoulders, curbs, road signs,
trees or other objects. Avoid jerky or sudden
maneuvers. Signal well in advance.
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Turn Signals When Towing a Trailer
The arrows on your instrument panel will
ash whenever you signal a turn or lane change.
Properly hooked up, the trailer lamps will also
ash, telling other drivers you’re about to
turn, change lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the
bulbs on the trailer are burned out. Thus, you may
think drivers behind you are seeing your signal
when they are not. It’s important to check
occasionally to be sure the trailer bulbs are
still working.
Driving On Grades
Reduce speed and shift to a lower gearbefore
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.
You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or a lower gear,
under heavy loads or hilly conditions.
When towing at high altitude on steep uphill
grades, consider the following: Engine coolant will
boil at a lower temperature than at normal
altitudes. If you turn your engine off immediately
after towing at high altitude on steep uphill grades,
your vehicle may show signs similar to engine
overheating. To avoid this, let the engine run while
parked (preferably on level ground) with the
automatic transmission in PARK (P) for a few
minutes before turning the engine off. If you do get
the overheat warning, seeEngine Overheating
on page 408.
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Parking on Hills
{CAUTION:
You really should not park your vehicle,
with a trailer attached, on a hill. If something
goes wrong, your rig could start to move.
People can be injured, and both your
vehicle and the trailer can be damaged.
But if you ever have to park your rig on a hill,
here’s how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet. When parking uphill, turn your
wheels away from the curb. When parking
downhill, turn your wheels into the curb.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release
the regular brakes until the chocks absorb
the load.
4. Reapply the regular brakes. Then apply your
parking brake, and then shift into PARK (P).
5. Release the regular brakes.
{CAUTION:
It can be dangerous to get out of your
vehicle if the shift lever is not fully in
PARK (P) with the parking brake rmly
set. Your vehicle can roll.
If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle
will not move, even when you are on fairly
level ground, use the steps that follow.
Always put the shift lever fully in PARK (P)
with the parking brake rmly set.
If the transfer case on four-wheel drive
vehicles is in NEUTRAL, your vehicle will
be free to roll, even if your shift lever is in
PARK (P). So, be sure the transfer case is
in a drive gear — not in NEUTRAL.
SeeFour-Wheel Drive on page 122.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal
down while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the
chocks.
4. Stop and have someone pick up and store
the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when
you’re pulling a trailer. See the Maintenance
Schedule for more on this. Things that are
especially important in trailer operation are
automatic transmission uid (don’t overll), engine
oil, axle lubricant, belt(s), cooling system and
brake system. Each of these is covered in
this manual, and the Index will help you nd them
quickly. If you’re trailering, it’s a good idea to
review these sections before you start your trip.
Check periodically to see that all hitch nuts
and bolts are tight.
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Trailer Wiring Harness
Your vehicle may be equipped with the seven-wire
trailer towing harness. This harness has a
seven-pin universal heavy-duty trailer connector
(if equipped with the trailering package) that is
attached to a bracket on the hitch platform. If your
vehicle is not equipped with the heavy-duty trailer
connector, you may purchase one from your dealer.The seven-wire harness contains the following
trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Running Lamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed
Dark Blue: Electric Brakes
If you need to tow a light-duty trailer with a
standard four-way round pin connector, an adapter
connector is available from your dealer.
If you are charging a remote (non-vehicle) battery,
turn on the headlamps to boost the vehicle
system voltage and properly charge the battery.
Your vehicle may also be equipped with wiring for
an electric trailer brake controller. These wires
are located inside the vehicle on the driver’s side
under the instrument panel. These wires should
be connected to an electric trailer brake controller
by your dealer or a qualied service center.
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✍NOTES
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Service........................................................ 380
Accessories and Modications................... 380
California Proposition 65 Warning.............. 381
Doing Your Own Service Work.................. 381
Adding Equipment to the Outside of
Your Vehicle.......................................... 382
Fuel............................................................. 382
Gasoline Octane........................................ 382
Gasoline Specications.............................. 383
California Fuel........................................... 383
Additives................................................... 383
Fuels in Foreign Countries........................ 384
Filling the Tank......................................... 385
Filling a Portable Fuel Container............... 387
Checking Things Under the Hood.............. 388
Hood Release........................................... 388
Engine Compartment Overview.................. 390
Engine Oil................................................. 394
Engine Oil Life System.............................. 398
Engine Air Cleaner/Filter............................ 400
Automatic Transmission Fluid.................... 401
Engine Coolant.......................................... 405Radiator Pressure Cap.............................. 408
Engine Overheating................................... 408
Cooling System......................................... 411
Engine Fan Noise..................................... 416
Power Steering Fluid ................................. 417
Windshield Washer Fluid........................... 418
Brakes...................................................... 419
Battery...................................................... 422
Jump Starting............................................ 423
Rear Axle.................................................... 428
Four-Wheel Drive........................................ 428
Front Axle................................................... 429
Bulb Replacement....................................... 430
Halogen Bulbs........................................... 430
Headlamps................................................ 431
Front Turn Signal, Sidemarker and
Parking Lamps....................................... 432
Taillamps, Turn Signal, and Stoplamps...... 432
Back-Up Lamps......................................... 434
License Plate Lamp................................... 435
Replacement Bulbs................................... 435
Section 5 Service and Appearance Care
377

Windshield Wiper Blade Replacement....... 436
Tires............................................................ 439
Tire Sidewall Labeling............................... 440
Tire Terminology and Denitions............... 444
Ination - Tire Pressure............................. 447
Tire Pressure Monitor System................... 448
Tire Inspection and Rotation...................... 453
When It Is Time for New Tires.................. 455
Buying New Tires...................................... 455
Different Size Tires and Wheels................ 457
Uniform Tire Quality Grading..................... 458
Wheel Alignment and Tire Balance............ 459
Wheel Replacement.................................. 460
Tire Chains............................................... 461
Accessory Inator...................................... 462
If a Tire Goes Flat.................................... 464
Changing a Flat Tire................................. 465
Removing the Spare Tire and Tools.......... 466
Removing the Flat Tire and Installing
the Spare Tire....................................... 469
Secondary Latch System........................... 475
Storing a Flat or Spare Tire and Tools...... 478
Spare Tire................................................. 481Appearance Care........................................ 482
Cleaning the Inside of Your Vehicle.......... 482
Fabric/Carpet............................................. 483
Leather...................................................... 484
Instrument Panel, Vinyl, and Other
Plastic Surfaces..................................... 485
Care of Safety Belts.................................. 485
Weatherstrips............................................ 485
Washing Your Vehicle............................... 486
Cleaning Exterior Lamps/Lenses................ 486
Finish Care............................................... 486
Windshield, Backglass, and
Wiper Blades......................................... 487
Aluminum Wheels...................................... 488
Tires......................................................... 488
Sheet Metal Damage................................. 489
Finish Damage.......................................... 489
Underbody Maintenance............................ 489
Chemical Paint Spotting............................ 489
Vehicle Care/Appearance Materials............ 490
Section 5 Service and Appearance Care
378

Vehicle Identication.................................. 491
Vehicle Identication Number (VIN)........... 491
Service Parts Identication Label............... 491
Electrical System........................................ 492
Add-On Electrical Equipment..................... 492
Headlamps................................................ 492
Windshield Wiper Fuses............................ 492Power Windows and Other Power
Options.................................................. 492
Fuses and Circuit Breakers....................... 493
Engine Compartment Fuse Block............... 493
Rear Underseat Fuse Block....................... 499
Capacities and Specications.................... 502
Section 5 Service and Appearance Care
379

Service
Your dealer knows your vehicle best and wants
you to be happy with it. We hope you will go
to your dealer for all your service needs. You will
get genuine GM parts and GM-trained and
supported service people.
We hope you will want to keep your GM vehicle
all GM. Genuine GM parts have one of these
marks:
Accessories and Modications
When you add non-GM accessories to your vehicle
they can affect your vehicle’s performance and
safety, including such things as, airbags, braking,
stability, ride and handling, emissions systems,
aerodynamics, durability, and electronic systems
like anti-lock brakes, traction control and
stability control. Some of these accessories may
even cause malfunction or damage not covered by
warranty.
GM Accessories are designed to complement and
function with other systems on your vehicle.
Your GM dealer can accessorize your vehicle
using genuine GM Accessories. When you go to
your GM dealer and ask for GM Accessories,
you will know that GM-trained and supported
service technicians will perform the work using
genuine GM Accessories.
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