2003 GMC ENVOY cooling system

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

Light (cont.)
Reduced Engine Power................................3-47
Safety Belt Reminder...................................3-37
Security.....................................................3-46
Service Four-Wheel-Drive Warning Light.........3-48
Loading Your Vehicle for Off-Road Driving..........4-16
Loading Your Vehicle.......................................4-47
Locking Rear Axle...........................................4-10
Lockout Protection..........................................2-12
Locks............................................................. 2-9
Delayed Locking........................................... 2-9
Door........................................................... 2-8
Leaving Your Vehicle....................................2-12
Lockout Protection.......................................2-12
Power Door.................................................. 2-9
Programmable Automatic Door Locks.............2-10
Rear Door Security Locks.............................2-12
Loss of Control...............................................4-14
Low Fuel Warning Light...................................3-50
Luggage Carrier..............................................2-48
Lumbar........................................................... 1-2
Power Controls............................................. 1-2
M
Maintenance, Normal Replacement Parts..........5-104
Maintenance Schedule.....................................6-11
At Each Fuel Fill.........................................6-11
At Least Once a Month................................6-11Maintenance Schedule (cont.)
At Least Once a Year..................................6-13
At Least Twice a Year..................................6-12
Brake System Inspection..............................6-17
Engine Cooling System Inspection.................6-17
Exhaust System Inspection...........................6-16
Fuel System Inspection................................6-16
How This Section is Organized....................... 6-3
Introduction.................................................. 6-2
Maintenance Requirements............................. 6-2
Part A - Scheduled Maintenance Services......... 6-4
Part B - Owner Checks and Services.............6-11
Part C - Periodic MaintenanceInspections......6-16
Part D - Recommended Fluids and
Lubricants...............................................6-18
Part E - Maintenance Record........................6-20
Scheduled Maintenance................................. 6-5
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection..........................6-16
Transfer Case and Front Axle (Four-Wheel
Drive) Inspection......................................6-17
Using Your................................................... 6-4
Your Vehicle and the Environment................... 6-2
Maintenance When Trailer Towing.....................4-59
Making Turns.................................................4-57
Malfunction Indicator Light................................3-42
Matching Transmitter(s) to Your Vehicle............... 2-6
Memory Seat.................................................2-51
9