2000 GMC ENVOY transmission oil

4-54 Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra
wiring and a heavy
-duty turn signal flasher.
The arrows on your instrument panel will flash
whenever you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you're about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will flash 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 gear before 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 should use THIRD (3) when towing a trailer.
Operating your vehicle in THIRD (3) when towing a
trailer will minimize heat buildup and extend the life of
your transmission. See ªTow/Haul Modeº in the Index.
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, see ªEngine Overheatingº in
the Index.
ProCarManuals.com

4-56 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 fluid (don't
overfill), engine oil, axle lubricant, belt, cooling system
and brake system. Each of these is covered in this
manual, and the Index will help you find 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.
Trailer Wiring Harness
The heavy-duty trailer wiring is an eight-wire harness
assembly. The harness is stored under the vehicle, on the
driver's side corner frame rear crossmember. The harness is
fused in the engine compartment fuse block. See ªFuses and
Circuit Breakersº in the Index. The harness does not have a
connector and should be wired by a qualified electrical
technician. The technician can use the following color code
chart when connecting the wiring harness to your trailer.

Dark Blue: Use for electric trailer brakes or
auxiliary wiring.

Red: Use for battery charging; it connects to the
starter solenoid.

Light Green: Back
-up lamps.

Brown: Taillamps and parking lamps.

Yellow: Left stoplamp and turn signal.

Dark Green: Right stoplamp and turn signal.

White: Ground wire.

Light Blue: Auxiliary stoplamp.
Securely attach the harness to the trailer, then tape or
strap it to your vehicle's frame rail. Be sure you leave it
loose enough so the wiring doesn't bend or break, but
not so loose that it drags on the ground. Store the
harness in its original place. Wrap the harness together
and tie it neatly so it won't be damaged.
ProCarManuals.com

6-
6-1
Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6
-2 Service
6
-3 Fuel
6
-5 Fuels in Foreign Countries
6
-5 Filling Your Tank
6
-7 Filling a Portable Fuel Container
6
-8 Checking Things Under the Hood
6
-10 Engine Oil
6
-15 Engine Air Cleaner/Filter
6
-16 Automatic Transmission Fluid
6
-19 Rear Axle
6
-20 Four-Wheel Drive
6
-21 Engine Coolant
6
-24 Radiator Pressure Cap
6
-25 Power Steering Fluid
6
-26 Windshield Washer Fluid
6
-27 Brakes6
-31 Battery
6
-31 Bulb Replacement
6
-35 Windshield Wiper Blade Replacement
6
-37 Tires
6
-45 Appearance Care
6
-46 Cleaning the Inside of Your Vehicle
6
-48 Care of Safety Belts
6
-50 Cleaning the Outside of Your Vehicle
6
-53 GM Vehicle Care/Appearance Materials
6
-54 Vehicle Identification Number (VIN)
6
-54 Service Parts Identification Label
6
-55 Electrical System
6
-60 Replacement Bulbs
6
-60 Capacities and Specifications
6
-61 Normal Maintenance Replacement Parts
ProCarManuals.com

6-9
When you lift the hood, you'll see these items:
A. Battery
B. Coolant Recovery Tank
C. Engine Oil Dipstick
D. Engine Oil FillE. Transmission Dipstick
F. Power Steering Reservoir
G. Brake Master Cylinder
H. Engine Air Cleaner/FilterI. Fuse Block
J. Windshield Washer
Fluid Reservoir
ProCarManuals.com

6-16
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission
fluid level is when the engine oil is changed.
Change both the fluid and filter every 15,000 miles
(25 000 km) if the vehicle is mainly driven under one
or more of these conditions:

In heavy city traffic where the outside temperature
regularly reaches 90F (32C) or higher.

In hilly or mountainous terrain.

When doing frequent trailer towing.

Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these conditions,
change the fluid and filter every 50,000 miles (83 000 km).
See ªScheduled Maintenance Servicesº in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at the dealership
service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
NOTICE:
Too much or too little fluid can damage your
transmission. Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire.
Be sure to get an accurate reading if you check
your transmission fluid.
ProCarManuals.com

6-59
Name Usage
LT TRN Left Turn Signal Rear
RT TRN Right Turn Signal Rear
RR PRK Right Rear Parking Lamps
TRL PRK Trailer Park Lamps
LT LOW Low
-Beam Headlamp, Left
RT LOW Low
-Beam Headlamp, Right
FRPRK Front Parking Lamps
INT BAT I/P Fuse Block Feed
ENG I Engine Sensors/Solenoids, MAF,
CAM, PURGE, VENT
ECM B Engine Control Module, Fuel
Pump, Module, Oil Pressure
ABS Anti
-Lock Brake System
ECM I Engine Control Module Injectors
A/C Air Conditioning
LT HI High
-Beam Headlamp, Left
RT HI High
-Beam Headlamp, RightName Usage
HORN Horn
BTSI Automatic Transmission Shift Lock
Control System
B/U LP Back
-Up Lamps
DRL Daytime Running Lamps
IGN B Column Feed, IGN 2, 3, 4
RAP Retained Accessory Power
LD LEV Electronic Load Leveling
OXYSEN Oxygen Sensor
IGN E Engine
MIR/LKS Mirrors, Door Locks
FOG LP Fog Lamps
IGN A Starting and Charging, IGN 1
STUD #2 Accessory Feeds, Electric Brake
PARKLP Parking Lamps
LR PRK Left Rear Parking Lamps
IGN C Starter Solenoid, Fuel Pump,
PRNDL
ProCarManuals.com

6-61 Capacities (Approximate)
Please refer to ªRecommended Fluids and Lubricantsº
in the Index for more information.
Cooling System* 11.7 quarts (11.1 L). . . . . . . . . . . . .
Crankcase* 4.5 quarts (4.3 L). . . . . . . . . . . . . . . . . . .
Automatic Transmission
(Drain and Refill)* 5.0 quarts (4.7 L). . . . . . . . . . .
Differential Fluid
Front 2.6 pints (1.2 L). . . . . . . . . . . . . . . . . . . . . . .
Rear 4.0 pints (1.9 L). . . . . . . . . . . . . . . . . . . . . . . .
Fuel Tank 18.0 gallons (68.0 L). . . . . . . . . . . . . . . . .
A/C Refrigerant See refrigerant charge label. . . . . .
under the hood.
*After refill, the level must be checked.
Normal Maintenance
Replacement Parts
Replacement part numbers listed in this section are based
on the latest information available at the time of printing,
and are subject to change. If a part listed in this manual is
not the same as the part used in your vehicle when it was
built, or if you have any questions, please contact your
GMC dealer.Thermostat 12559051. . . . . . . . . . . . . . . . . . . . . . . . .
Oil Filter PF52. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Cleaner Filter A1163C. . . . . . . . . . . . . . . . . . . . . .
PCV Valve CV769C. . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Transmission
Filter Kit 24200796. . . . . . . . . . . . . . . . . . . . . . . . .
Spark Plugs 41
-932 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel Filter GF481. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Front Windshield
Wiper Blade Trico (20 inches/50.8 cm). . . . . . . . . .
Backglass Wiper Blade Trico (14 inches/35.6 cm) . . . .
Vehicle Dimensions
Wheelbase 107.0 inches (271.8 cm). . . . . . . . . . . . . .
Length 181.5 inches (460.0 cm). . . . . . . . . . . . . . . . .
Height 67.0 inches (170.2 cm). . . . . . . . . . . . . . . . . . .
Width 67.8 inches (172.2 cm). . . . . . . . . . . . . . . . . . .
Front Tread 57.3 inches (145.4 cm). . . . . . . . . . . . . . .
Rear Tread 55.1 inches (139.9 cm). . . . . . . . . . . . . . .
ProCarManuals.com

Scheduled Maintenance
7-5
Short Trip/City Definition
Follow the Short Trip/City Scheduled Maintenance if
any one of these conditions is true for your vehicle:

Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.

Most trips include extensive idling (such as frequent
driving in stop
-and-go traffic).

You operate your vehicle in dusty areas or
off
-road frequently.

You frequently tow a trailer or use a carrier on top
of your vehicle.

If the vehicle is used for delivery service, police, taxi
or other commercial application.
One of the reasons you should follow this schedule if
you operate your vehicle under any of these conditions
is that these conditions cause engine oil to break
down sooner.
Short Trip/City Intervals
Every 3,000 Miles (5 000 km): Engine Oil and Filter
Change (or 3 months, whichever occurs first). Chassis
Lubrication (or 3 months, whichever occurs first).
Drive Axle Service (or 3 months, whichever
occurs first).
Every 6,000 Miles (10 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Engine Air Cleaner
Filter Inspection, if driving in dusty conditions.
Automatic Transmission Service (severe
conditions only).
Every 30,000 Miles (50 000 km): Engine Air Cleaner
Filter Replacement. Fuel Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (normal conditions).
(Continued)
ProCarManuals.com