cooling system GMC ENVOY 2003 Owner's Guide

6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
®ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
žcoolant mixture
through the ®ller neck until the level reaches
the base of the ®ller neck.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to ¯ow out of the
®ller neck, reinstall the pressure cap. Be sure
the pressure cap is hand-tight.
Engine Fan Noise
This vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions the clutch is not engaged. This improves fuel
economy and reduces fan noise. Under heavy vehicle
loading, trailer towing, and/or high outside temperatures,
the fan speed increases when the clutch engages. So
you may hear an increase in fan noise. This is
normal and should not be mistaken as the transmission
slipping or making extra shifts. It is merely the cooling
system functioning properly. The fan will slow down
when additional cooling is not required and the clutch
disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
5-35

Fuses Usage
1Electrically-Controlled Air
Suspension
2Passenger's Side High-Beam
Headlamp
3Passenger's Side Low-Beam
Headlamp
4 Back-Up-Trailer Lamps
5 Driver's Side High-Beam Headlamp
6 Driver's Side Low-Beam Headlamp
7 Wash
8 Automatic Transfer Case
9 Windshield Wipers
10 Powertrain Control Module B
11 Fog Lamps
12 Stop Lamp
13 Cigarette Lighter
14 Ignition Coils
15 Air Suspension Ride
16 TBD-Ignition 1Fuses Usage
17 Crank
18 Air Bag
19 Electric Brake
20 Cooling Fan
21 Horn
22 Ignition E
23 Electronic Throttle Control
24Instrument Panel Cluster, Driver
Information Center
25 Automatic Shift Lock Control System
26 Engine 1
27 Back-Up
28 Powertrain Control Module 1
29 Oxygen Sensor
30 Air Conditioning
31 Truck Body Controller
32 Trailer
33 Anti-Lock Brakes (ABS)
5-93

Fuses Usage
1Electrically-Controlled Air
Suspension
2Passenger's Side High-Beam
Headlamp
3Passenger's Side Low-Beam
Headlamp
4 Back-Up-Trailer Lamps
5 Driver's Side High-Beam Headlamp
6 Driver's Side Low-Beam Headlamp
7 Wash
8 Automatic Transfer Case
9 Windshield Wipers
10 Powertrain Control Module B
11 Fog Lamps
12 Stop Lamp
13 Cigarette Lighter
14 Ignition Coils
15 Cannister Vent
16 TBD-Ignition 1
17 Crank
18 Air Bag
19 Electric Brake
20 Cooling Fan
21 HornFuses Usage
22 Ignition E
23 Electronic Throttle Control
24Instrument Panel Cluster, Driver
Information Center
25 Automatic Shift Lock Control System
26 Engine 1
27 Back-Up
28 Powertrain Control Module 1
30 Air Conditioning
31 Truck Body Controller 1
32 Trailer
33 Anti-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger's Side Trailer Turn
51 Driver's Side Trailer Turn
52 Hazard Flashers
53 Oxygen Sensor Bank A
54 Oxygen Sensor Bank B
55 Injector Bank A
56 Injector Bank B
Relays Usage
37 Headlamp Washer
5-96

Capacities and Speci®cations
Capacities and Speci®cations
Engine VIN Code Transmission Spark Plug Gap Firing Order
ªVORTECŸ º 4200 L6 S M300.042 inches
(1.07 mm)1±5-3±6±2±4
ªVORTECŸ º 5300 V8 P M300.060 inches
(1.52 mm)1±8±7±2±6±5±4±3
ApplicationL6 Engine V8 Engine
English Metric English Metric
Wheel Nut Torque 100 lb ft 140Y100 lb ft 140Y
Cooling System
Envoy 13.9 quarts 13.1 L Ð Ð
Envoy XL 15.2 quarts 14.4 L 17.9 quarts 17.0 L
Air Conditioning Refrigerant R/134a
Envoy 1.9 lbs. 0.9 kg Ð Ð
Envoy XL 2.8 lbs. 1.27 kg 2.8 lbs. 1.27 kg
Engine Oil with Filter 7.0 quarts 6.6 L 6.0 quarts 5.7 L
5-102

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Your Vehicle and the Environment....................6-2
Maintenance Requirements..............................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-11
At Each Fuel Fill..........................................6-11
At Least Once a Month.................................6-11
At Least Twice a Year...................................6-12At Least Once a Year...................................6-13
Part C: Periodic MaintenanceInspections.........6-16
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection............................6-16
Exhaust System Inspection............................6-16
Fuel System Inspection..................................6-16
Engine Cooling System Inspection...................6-17
Transfer Case and Front Axle (Four-Wheel
Drive) Inspection.......................................6-17
Brake System Inspection................................6-17
Part D: Recommended Fluids and Lubricants. . . .6-18
Part E: Maintenance Record...........................6-20
Section 6 Maintenance Schedule
6-1

100,000 Miles (166 000 km)
qV8 Engine Only: Inspect spark plug wires.An
Emission Control Service.
qReplace spark plugs.An Emission Control Service.
qChange automatic transmission ¯uid and ®lter if
the vehicle is mainly driven under one or more
of these conditions:
þ In heavy city traffic where the outside
temperature regularly reaches 90ÉF (32ÉC) or
higher.
þ In hilly or mountainous terrain.
þ When doing frequent trailer towing.
þ Uses such as found in taxi, police or delivery
service.
qIf you haven't used your vehicle under severe service
conditions listed previously and, therefore, haven't
changed your automatic transmission ¯uid, change
both the ¯uid and ®lter
qAutomatic Transfer Case Only: Change transfer case
¯uid.
qV8 Engine Only: Inspect Positive Crankcase
Ventilation (PCV) valve.
An Emission Control Service.
150,000 Miles (240 000 km)
qDrain, ¯ush and re®ll cooling system (or every
60 months since last service, whichever occurs ®rst).
See
Engine Coolant on page 5-24for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap and neck. Pressure test the cooling system
and pressure cap.
An Emission Control Service.
qInspect engine accessory drive belt.An Emission
Control Service.
6-10

Engine Cooling System Inspection
Inspect the hoses and have them replaced if they
are cracked, swollen or deteriorated. Inspect all pipes,
®ttings and clamps; replace as needed. Clean the
outside of the radiator and air conditioning condenser.
To help ensure proper operation, a pressure test of
the cooling system and pressure cap is recommended
at least once a year.
Transfer Case and Front Axle
(Four-Wheel Drive) Inspection
Every 12 months or at engine oil change intervals,
check front axle and transfer case and add lubricant
when necessary. A ¯uid loss could indicate a problem;
check and have it repaired, if needed. Check vent
hose at transfer case for kinks and proper installation.
More frequent lubrication may be required on
off-road use.
Brake System Inspection
Inspect the complete system. Inspect brake lines and
hoses for proper hook-up, binding, leaks, cracks,
cha®ng, etc. Inspect disc brake pads for wear and rotors
for surface condition. Inspect other brake parts,
including calipers, parking brake, etc. Check parking
brake adjustment. You may need to have your brakes
inspected more often if your driving habits or
conditions result in frequent braking.
6-17

Convenience Net............................................2-49
Coolant.........................................................3-41
Engine Temperature Gage............................3-41
Heater, Engine............................................2-22
Cooling System..............................................5-29
Cruise Control Light........................................3-47
Cruise Control................................................3-12
Current and Past Model Order Forms................7-11
Customer Assistance Information........................ 7-7
Courtesy Transportation.................................. 7-7
Customer Assistance for Text Telephone
(TTY) Users.............................................. 7-4
Customer Assistance Offices........................... 7-4
Customer Satisfaction Procedure..................... 7-2
GM Mobility Program for Persons with
Disabilities................................................ 7-5
Reporting Safety Defects to General Motors....7-10
Reporting Safety Defects to the Canadian
Government.............................................. 7-9
Reporting Safety Defects to the United
States Government.................................... 7-9
Roadside Assistance Program......................... 7-5
Service Publications Ordering Information........7-10
D
Daytime Running Lamps (DRL).........................3-16
Defensive Driving............................................. 4-2
Defogging and Defrosting.........................3-22, 3-27Delayed Locking............................................... 2-9
Dinghy Towing................................................4-46
Doing Your Own Service Work........................... 5-3
Dome Lamp Override......................................3-18
Dome Lamps.................................................3-19
Door............................................................... 2-9
Delayed Locking........................................... 2-9
Locks.......................................................... 2-8
Power Door Locks......................................... 2-9
Programmable Automatic Door Locks.............2-10
Rear Door Security Locks.............................2-12
DRIVER DOOR AJAR.....................................3-62
Driver Information Center (DIC).........................3-50
DIC Operation and Displays..........................3-51
DIC Warnings and Messages........................3-60
Driver............................................................1-14
Position, Safety Belt.....................................1-14
Driving Across an Incline..................................4-24
Driving Downhill..............................................4-23
Driving in Mud, Sand, Snow or Ice....................4-26
Driving in Water..............................................4-27
Driving On Grades..........................................4-58
Driving on Off-Road Hills.................................4-19
Driving on Snow or Ice....................................4-40
Driving Through Deep Standing Water...............4-31
Driving Through Flowing Water.........................4-32
Driving Uphill..................................................4-20
Driving with a Trailer.......................................4-56
Driving..........................................................4-28
At Night.....................................................4-28
4

Driving (cont.)
City...........................................................4-33
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-34
Hill and Mountain Roads..............................4-37
In Rain and on Wet Roads...........................4-30
Winter........................................................4-39
Dual Automatic Climate Control System.............3-24
Dual Climate Control System............................3-21
DVD Player....................................................3-95
DVD ............................................................3-107
Cleaning the Video Screen..........................3-107
Distortion..................................................3-105
Rear Seat Entertainment System...................3-92
E
Electrical System............................................5-89
Add-On Equipment......................................5-89
Fuses and Circuit Breakers...........................5-90
Headlamps.................................................5-89
Power Windows and Other Power Options......5-90
Windshield Wiper Fuses...............................5-89
Electronically Controlled Air Suspension
System......................................................4-49
Emergency Release for Opening Liftgate............2-13
Emissions Inspection and Maintenance
Programs...................................................3-44Engine Compartment Fuse Block......................5-91
ENGINE COOLANT HOT/IDLE ENGINE.............3-60
Engine Coolant Level Check.............................6-11
Engine Oil Additives........................................5-18
Engine Oil Level Check...................................6-11
Engine Oil Scheduled Maintenance..................... 6-5
Engine..........................................................5-20
Air Cleaner/Filter.........................................5-20
Battery.......................................................5-41
Change Engine Oil Light...............................3-46
Check and Service Engine Soon Light............3-42
Compartment Overview................................5-12
Coolant Heater............................................2-22
Coolant Temperature Gage...........................3-41
Coolant......................................................5-24
Cooling System Inspection............................6-17
Exhaust.....................................................2-33
Fan Noise..................................................5-35
Oil .............................................................5-15
Overheating................................................5-27
Reduced Power Light...................................3-47
Starting......................................................2-21
Entertainment System....................................3-107
Cleaning the Video Screen..........................3-107
DVD Distortion..........................................3-105
Entry Lighting.................................................3-18
Environmental Concerns..................................4-17
Erasing HomeLink
žButtons..............................2-43
Exit Lighting...................................................3-18
Express±Down Window....................................2-16
5

Inspection......................................................6-17
Brake System.............................................6-17
Engine Cooling System................................6-17
Exhaust System..........................................6-16
Fuel System...............................................6-16
Part C - Periodic Maintenance.......................6-16
Steering, Suspension and Front Drive Axle
Boot and Seal.........................................6-16
Transfer Case and Front Axle
(Four-Wheel Drive)...................................6-17
Instrument Panel Brightness.............................3-17
Instrument Panel.............................................3-35
Cluster.......................................................3-35
Overview..................................................... 3-4
Interior Lamps................................................3-17
J
Jump Starting.................................................5-42
K
Key Lock Cylinders Service..............................6-13
Keyless Entry System....................................... 2-5
Keys............................................................... 2-3
L
Lamps On Reminder.......................................3-16
Lamps...........................................................3-15
Exterior......................................................3-15
Interior.......................................................3-17
Lap-Shoulder Belt...................................1-15, 1-24
LATCH System...............................................1-42
Child Restraints...........................................1-42
Securing a Child Restraint Designed for
the LATCH System...................................1-44
Leaving Your Vehicle With the Engine
Running.....................................................2-30
Leaving Your Vehicle.......................................2-12
LEFT REAR DOOR AJAR................................3-62
Liftgate Release..............................................2-13
Liftgate/Liftglass..............................................2-13
Liftglass/Liftgate..............................................2-13
Lighted Visor Vanity Mirror...............................2-16
Light.............................................................3-37
Air Bag Readiness.......................................3-37
Anti-Lock Brake System Warning...................3-41
Brake System Warning.................................3-39
Change Engine Oil......................................3-46
Charging System.........................................3-38
Check Gages Warning.................................3-48
Cruise Control.............................................3-47
Gate Ajar...................................................3-49
Low Fuel Warning.......................................3-50
Malfunction Indicator....................................3-42
8