2004 GMC ENVOY XL radiator cap

How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap when
the cooling system, including the radiator pressure
cap and upper radiator hose, is no longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.2. Then keep turning the pressure cap. Remove the
pressure cap.
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3. Fill the radiator with the proper DEX-COOL®
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.
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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
®coolant 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.
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Maintenance Footnotes
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chang, etc. Inspect
disc brake pads for wear and rotors for surface
condition. Inspect other brake parts, including calipers,
parking brake, etc.
(b)Visually inspect front and rear suspension and
steering system for damaged, loose or missing parts
or signs of wear. Inspect power steering lines and hoses
for proper hook-up, binding, leaks, cracks, chang,
etc.
(c)Visually inspect hoses and have them replaced if they
are cracked, swollen or deteriorated. Inspect all pipes,
ttings and clamps; replace with genuine GM parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.(d)Visually inspect wiper blades for wear or cracking.
Replace blade inserts that appear worn or damaged
or that streak or miss areas of the windshield.
(e)Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced. Also look for any opened or broken air bag
coverings, and have them repaired or replaced. (The air
bag system does not need regular maintenance.)
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer liftgate handle pivot
points, rear door detent link, roller mechanism, liftgate
handle pivot points, latch bolt, fuel door hinge, cargo
door hinge, locks and folding seat hardware. More
frequent lubrication may be required when exposed to
a corrosive environment. Applying silicone grease
on weatherstrips with a clean cloth will make them last
longer, seal better and not stick or squeak.
(g)Add uid as needed. A uid loss could indicate a
problem; repair as needed. Check vent hose at transfer
case for kinks and proper installation.
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(h)Change automatic transmission uid and lter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
(i)Drain, ush and rell cooling system. See Engine
Coolant on page 5-24for what to use. Inspect hoses.
Clean radiator, condenser, pressure cap and ller neck.
Pressure test the cooling system and pressure cap.
(j)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the uid level checked. Add uid if needed.Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability and emission control performance of your
vehicle. Your GM Goodwrench dealer can assist you
with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
6-9

Power Steering...............................................4-11
Programmable Automatic Door Locks.................2-10
Programmable Locking Feature.........................2-11
Programmable Unlocking Feature......................2-12
Programming the HomeLink
®Transmitter...........2-43
Q
Questions and Answers About Safety Belts.........1-13
R
Radiator Pressure Cap....................................5-27
Radio Data System (RDS)...............3-65, 3-76, 3-92
Radio Messages.....................................3-71, 3-83
Radios..........................................................3-64
Care of Your Cassette Tape Player...............3-121
Care of Your CD and DVD Player................3-122
Care of Your CDs and DVDs.......................3-122
Navigation/Radio System.............................3-106
Radio Personalization.................................3-119
Radio with Cassette and CD.........................3-76
Radio with CD............................................3-65
Radio with Six-Disc CD................................3-92
Rear Seat Audio........................................3-117
Setting the Time..........................................3-64
Theft-Deterrent..........................................3-119
Understanding Reception............................3-120Rainsense™ Wipers........................................3-10
RDS Messages..............................3-70, 3-82, 3-97
Reading Lamps..............................................3-20
REAR ACCESS OPEN....................................3-62
Rear Axle......................................................5-48
Locking......................................................4-11
Rear Climate Control System............................3-31
Rear Compartment Storage Panel/Cover............2-49
Rear Door Security Locks................................2-13
Rear Floor Storage Lid....................................2-51
Rear Safety Belt Comfort Guides......................1-24
Rear Seat Audio (RSA)..................................3-117
Rear Seat Entertainment System.....................3-106
Rear Seat Operation......................................... 1-5
Rear Seat Passenger Positions.........................1-21
Rear Seat Passengers, Safety Belts..................1-21
Rear Seats (Envoy XL)..................................... 1-7
Rear Storage Area..........................................2-49
Rear Underseat Fuse Block............................5-104
Rear Window Defogger............................3-24, 3-29
Rearview Mirror, Automatic Dimming
with OnStar
®and Compass..........................2-36
Reclining Seatbacks, Power............................... 1-4
Recommended Fluids and Lubricants.................6-13
Recreational Vehicle Towing.............................4-45
Reduced Engine Power Light............................3-48
Remote Control.............................................3-112
Remote Keyless Entry System............................ 2-5
Remote Keyless Entry System, Operation............ 2-6
11