2007 GMC ENVOY service

Here are some things you can check before a trip:
Windshield Washer Fluid:Is the reservoir
full? Are all windows clean inside and outside?
Wiper Blades:Are they in good shape?
Fuel, Engine Oil, Other Fluids:Have you
checked all levels?
Lamps:Are they all working? Are the lenses
clean?
Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough
for long-distance driving? Are the tires
all inated to the recommended pressure?
Weather Forecasts:What is the weather
outlook along your route? Should you
delay your trip a short time to avoid a major
storm system?
Maps:Do you have up-to-date maps?
Highway Hypnosis
Is there actually such a condition as highway
hypnosis? Or is it just plain falling asleep at the
wheel? Call it highway hypnosis, lack of
awareness, or whatever.
There is something about an easy stretch of road
with the same scenery, along with the hum of the
tires on the road, the drone of the engine, and the
rush of the wind against the vehicle that can make
you sleepy. Do not let it happen to you! If it does,
your vehicle can leave the road in less than a
second, and you could crash and be injured.
What can you do about highway hypnosis?
First, be aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with
a comfortably cool interior.
Keep your eyes moving. Scan the road ahead
and to the sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get
some exercise, or both. For safety, treat
drowsiness on the highway as an emergency.
341

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

Overload Protection
The air suspension system is equipped with
overload protection. Overload protection is
designed to protect the air suspension system,
and it is an indicator to the driver that the vehicle
is overloaded. When the overload protection
mode is on, it will not allow damage to the
air compressor. However, do not overload the
vehicle. SeeLoading Your Vehicle on page 349.
If the suspension remains at a low height, the rear
axle load has exceeded GAWR (Gross Axle
Weight Rating). When the overload protection
mode is activated, the compressor operates
for about 30 seconds to one minute without raising
the vehicle depending on the amount of overload.
This will continue each time the ignition is
turned on until the rear axle load is reduced
below GAWR.
Indicator Light
The indicator light on the inator switch in the rear
passenger compartment also serves as an
indicator for internal system error. If the indicator
light is ashing without the load leveling function
or the inator being active, turn off the ignition.
The next day turn on the ignition and check
the indicator light. The vehicle can be driven with
the light ashing, but if it is you should have
the vehicle serviced as soon as possible.
361

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.
374

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.
375

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