2003 GMC ENVOY radiator cap

3. Fill the radiator with the proper DEX-COOLž
coolant mixture, up to the base of the ®ller
neck. SeeEngine Coolant on page 5-24for more
information about the proper coolant mixture.4. Then ®ll the coolant recovery tank to the FULL
COLD mark.
5. Put the cap back on the coolant recovery tank, but
leave the radiator pressure cap off.
5-34

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

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

P
Park(P).........................................................2-29
Shifting Into................................................2-29
Shifting Out of............................................2-31
Parking Brake and Automatic Transmission
Park (P) Mechanism Check...........................6-15
Parking on Hills..............................................4-58
Parking.........................................................2-28
Brake........................................................2-28
Over Things That Burn.................................2-32
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
PASSENGER DOOR AJAR..............................3-62
Passing.................................................4-12, 4-57
Passlock
ž......................................................2-18
Personalization, Climate Controls......................3-33
Personalization...............................................3-53
Plan Ahead When Possible................................ 7-7
Playing a Cassette Tape..................................3-77
Playing a Compact Disc..................3-69, 3-79, 3-87
Playing a Speci®c Loaded Compact Disc............3-88
Playing the Radio...........................3-64, 3-71, 3-81
Power Steering...............................................4-10
Power...........................................................3-19
Accessory Outlets........................................3-19
Door Locks.................................................. 2-9Power (cont.)
Electrical System.........................................5-90
Lumbar Controls........................................... 1-2
Reclining Seatbacks...................................... 1-4
Reduced Engine Light..................................3-47
Seat............................................................ 1-2
Steering Fluid.............................................5-36
Windows....................................................2-15
Programmable Automatic Door Locks.................2-10
Programmable Locking Feature.........................2-10
Programmable Unlocking Feature......................2-11
Programming the HomeLink Transmitter.............2-41
Q
Questions and Answers About Safety Belts.........1-13
R
Radiator Pressure Cap....................................5-26
Radio Messages.....................................3-69, 3-76
Radios..........................................................3-63
Care of Your Cassette Tape Player...............3-106
Care of Your CD and DVD Player................3-107
Care of Your CDs and DVDs.......................3-107
Radio Personalization.................................3-104
Radio with Cassette and CD.........................3-71
Radio with CD............................................3-64
Radio with Six-Disc CD................................3-81
11