tow GMC ENVOY 2003 Repair Manual

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

GM Mobility Program for Persons
with Disabilities
This program, available to
quali®ed applicants, can
reimburse you up to
$1,000 toward aftermarket
driver or passenger
adaptive equipment you
may require for your
vehicle (hand controls,
wheelchair/scooter
lifts, etc.).
This program can also provide you with free resource
information, such as area driver assessment centers and
mobility equipment installers. The program is available
for a limited period of time from the date of vehicle
purchase/lease. See your dealer for more details or call
the GM Mobility Assistance Center at 1-800-323-9935.
Text telephone (TTY) users, call 1-800-833-9935.
GM of Canada also has a Mobility Program. Call
1-800-GM-DRIVE (463-7483) for details. All TTY users
call 1-800-263-3830.
Roadside Assistance Program
GMC's Roadside Assistance Provides stranded owners
with over-the-phone roadside repairs, location of the
nearest GMC dealer or the following special services:
Flat Tire Change:Installation of spare tire will be
covered at no charge (customer is responsible for repair
or replacement of tire).
Fuel Delivery:Delivery of enough fuel for the customer
to get to the nearest service station (up to $5.00)
will be covered.
Jump Start:No-start situations which require a battery
jump start will be covered at no charge.
Lock Out:Replacement keys or locksmith service will be
covered at no charge if you are unable to gain entry
into your vehicle. Delivery of the replacement key will be
covered within 10 miles (16 km).
Emergency Towing Service:Towing to the nearest GMC
dealer for warranty related disablements will be
covered.
7-5

Reporting Safety Defects
Reporting Safety Defects to the
United States Government
If you believe that your vehicle has a defect which could
cause a crash or could cause injury or death, you
should immediately inform the National Highway Traffic
Safety Administration (NHTSA), in addition to notifying
General Motors.
If NHTSA receives similar complaints, it may open an
investigation, and if it ®nds that a safety defect exists in
a group of vehicles, it may order a recall and remedy
campaign. However, NHTSA cannot become involved in
individual problems between you, your dealer or
General Motors.
To contact NHTSA, you may either call the Auto Safety
Hotline toll-free at 1-800-424-9393 (or 366-0123 in
the Washington, D.C. area) or write to:
NHTSA, U.S. Department of Transportation
Washington, D.C. 20590
You can also obtain other information about motor
vehicle safety from the hotline.
Reporting Safety Defects to the
Canadian Government
If you live in Canada, and you believe that your vehicle
has a safety defect, you should immediately notify
Transport Canada, in addition to notifying General
Motors of Canada Limited. You may write to:
Transport Canada
330 Sparks Street
Tower C
Ottawa, Ontario K1A 0N5
7-9

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

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

Radios (cont.)
Rear Seat Audio........................................3-103
Setting the Time..........................................3-63
Theft-Deterrent..........................................3-104
Understanding Reception............................3-105
RainsenseŸ Wipers........................................3-10
RDS Messages..............................3-68, 3-75, 3-86
Reading Lamps..............................................3-19
REAR ACCESS OPEN....................................3-61
Rear Axle......................................................5-48
Locking......................................................4-10
Rear Climate Control System............................3-29
Rear Compartment Storage Panel/Cover............2-46
Rear Door Security Locks................................2-12
Rear Floor Storage Lid....................................2-49
Rear Safety Belt Comfort Guides......................1-26
Rear Seat Audio (RSA)..................................3-103
Rear Seat Entertainment System.......................3-92
Rear Seat Operation......................................... 1-6
Rear Seat Passenger Positions.........................1-23
Rear Seat Passengers, Safety Belts..................1-23
Rear Seats (Envoy XL)..................................... 1-7
Rear Underseat Fuse Block..............................5-97
Rear Window Defogger............................3-23, 3-27
Rearview Mirror, Automatic Dimming with
OnStar
žand Compass.................................2-35
Reclining Seatbacks, Power............................... 1-4
Recreational Vehicle Towing.............................4-45
Reduced Engine Power Light............................3-47Remote Control..............................................3-97
Remote Keyless Entry System, Operation............ 2-6
Remote Keyless Entry System............................ 2-5
Removing the Flat Tire and Installing the
Spare Tire..................................................5-72
Removing the Spare Tire and Tools...................5-66
Replacement Bulbs.........................................5-52
Replacing Brake System Parts..........................5-41
Replacing Restraint System Parts
After a Crash..............................................1-61
Reporting Safety Defects................................... 7-9
Canadian Government................................... 7-9
General Motors...........................................7-10
United States Government.............................. 7-9
Reprogramming a Single HomeLink
žButton.......2-43
Resetting Defaults...........................................2-44
Restraint System Check...................................6-12
Checking Your Restraint Systems...................1-60
Replacing Restraint System Parts
After a Crash..........................................1-61
Restraint Systems...........................................1-60
Checking....................................................1-60
Replacing Parts...........................................1-61
Retained Accessory Power (RAP)......................2-20
RFA # BATTERY LOW....................................3-62
Right Front Passenger Position, Safety Belts......1-22
RIGHT REAR DOOR AJAR..............................3-62
Roadside......................................................... 7-5
Assistance Program....................................... 7-5
12

Top Strap Anchor Location...............................1-41
Top Strap......................................................1-40
Torque Lock...................................................2-31
Total Weight on Your Vehicle's Tires..................4-54
Towing..........................................................4-45
Recreational Vehicle.....................................4-45
Towing a Trailer..........................................4-50
Your Vehicle...............................................4-45
Traction........................................................... 4-8
Assist System (TAS)...................................... 4-8
Trailer Brakes.................................................4-55
Trailer Wiring Harness.....................................4-60
TRANS HOT IDLE ENGINE.............................3-61
Transfer Case and Front Axle
(Four-Wheel Drive) Inspection.......................6-17
Transfer Case................................................5-48
Transmission Operation, Automatic....................2-23
Transmission, Transaxle, Transfer Case Unit
Repair Manual............................................7-10
Transmission..................................................5-21
Fluid, Automatic...........................................5-21
Transportation Options...................................... 7-7
Travel Note Recorder......................................2-45
Traveling to Remote Areas...............................4-17
Trip Information..............................................3-51
Trip Odometer................................................3-36
Turn and Lane Change Signals.......................... 3-8
TURN SIGNAL ON.........................................3-61
Turn Signal/Multifunction Lever........................... 3-7Turn Signals When Towing a Trailer..................4-57
Two-Wheel-Drive Vehicles................................4-46
U
Underbody Flushing Service.............................6-15
Understanding Radio Reception.......................3-105
Uniform Tire Quality Grading............................5-59
United States................................................... 7-4
Used Replacement Wheels..............................5-61
Using Cleaner on Fabric..................................5-81
Using HomeLink
ž...........................................2-43
Using RDS....................................3-67, 3-74, 3-84
Using Song List Mode.....................................3-90
V
Vehicle Identi®cation........................................5-88
Number (VIN).............................................5-88
Service Parts Identi®cation Label...................5-88
Vehicle Personalization....................................2-51
Memory Seat..............................................2-51
Vehicle Storage..............................................5-42
Vehicle............................................................ 4-5
Control........................................................ 4-5
Damage Warnings........................................... iv
Loading......................................................4-47
Symbols......................................................... iv
15