1998 GMC ENVOY radiator

Remote Oil Filter
The access door for the remote oil filter is in the steering
linkage shield assembly located under the radiator
support. Twist the screw to unlock or lock the door.
If
you open the door, make sure it is securely closed when
you are finished.
What to Do with Used Oil
Did you know that used engine oil contains certain
elements
that may be unhealthy for your skin and could
even cause cancer? Don’t let used oil stay on your skin
for very long. Clean your skin and nails with soap and
water, or
a good hand cleaner. Wash or properly throw
away clothing or rags containing used engine oil. (See
the manufacturer’s warnings about the use and disposal
of oil products.)
Used oil can be a real threat to the environment. If you
change your own oil, be sure to drain all free-flowing oil
from the filter before disposal. Don’t ever dispose of oil
by putting
it in the trash, pouring it on the ground, into
sewers, or into streams or bodies
of water. Instead,
recycle it by taking it to
a place that collects used oil. If
you have a problem properly disposing of your used oil,
ask your dealer, a service station or a local recycling
center for help.
To remove the air cleaner, remove the wing nuts that
hold the cover on. Remove the cover and lift
out the
air filter.
Insert
a new air filter, then replace the air cleaner cover.
Tighten the wing nuts
to hold the cover in place.
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A 50/50 mixture of water and DEX-COOL@ coolant will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F ( 129°C).
0 Protect against rust and corrosion.
0 Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
NOTICE:
When adding coolant, it is important that you use
only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
0- at
30,000 miles (50 000 km) or 24 months,
whichever occurs
first. Damage caused by the use
of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum
parts. If you use this mixture,
you don’t need to add anything else.
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn’t
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use
a 50/50 mixture of clean water and
DEX-COOL@ coolant.
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NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty.
Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to
add extra inhibitors or additives which claim to
improve the system. These can be harmful.
Checking Coolant
When your engine is cold, the coolant level should be at
ADD, or a little higher. When your engine is warm, the
level should be up to
FULL HOT, or a little higher.
Adding Coolant
If you need more coolant, add the proper DEX-COOL@
coolant mixture at the cwolarzt recovery tank.
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-
A CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam and
scalding liquids to blow out and burn
you badly.
With the coolant recovery tank, you
will almost
never have to add coolant
at the radiator. Never
turn the radiator pressure cap
-- even a
little
-- when the engine and radiator are hot.
Add coolant mixture at the recovery tank, but be careful
not to spill it.
A CAUTION:
I
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn
if the engine parts are hot
enough. Don’t spill coolant on
a hot engine.
Radiator Pressure Cap
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure-type cap and must be tightly installed to
prevent coolant
loss and possible engine damage
from overheating. Be sure the arrows on the cap
line
up with the overflow tube on the radiator
filler neck.
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Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine coolant system. The thermostat stops the
flow
of coolant through the radiator until the coolant
reaches a preset temperature.
Power Steering Fluid
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless you suspect there is
a leak in the system or
you hear an unusual noise.
A fluid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How To Check Power Steering Fluid
When the engine compartment is cool, wipe the cap and
the top
of the reservoir clean, then unscrew the cap and
wipe the dipstick with a clean rag. Replace the cap and
completely tighten it. Then remove the cap again and
look at the fluid level on the dipstick.
The level should be between the
ADD and FULL marks.
If necessary, add only enough fluid to bring the level up
to the proper range.
What to Use
To determine what kind of fluid to use, see
“Recommended Fluids and Lubricants” in the Index.
Always use the proper fluid. Failure to use the proper
fluid can cause leaks and damage hoses and seals.
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I Short Trip/City Maintenance Schedule I
100,000 Miles (I66 000 km)
17 Inspect spark plug wires.
0 Replace spark plugs.
0 If you haven’t used your vehicle under severe service conditions listed
AFI Emission Control Service.
An Emission Control Service.
previously and, therefore, haven’t changed your autornatic transmission fluid,
change both the fluid and filter.
An Errzission Cmtd Service.
0 Inspect Positive Crankcase Ventilation (PCV) valve.
150,000 Miles (240 000 km)
0 Drain, flush and refill cooling system (or every 60 months since last service,
whichever occurs first). See “Engine Coolant”
in the Index for what to use.
Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure
test
cooling system and pressure cap.
An Ernission Control Service.
DATE I
DATE I
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Long Tripmighway Maintenance Schedule
100,000 Miles (166 000 km)
0 Inspect spark plug wires.
0 Replace spark plugs.
0 If you haven't used your vehicle under severe service conditions listed
An Emission Control Service.
API Emission Control Service.
previously and, therefore, haven't changed your automatic transmission fluid,
change both the fluid and filter.
An Emission Control Service.
Inspect Positive Crankcase Ventilation (PCV) valve.
150,000 Miles (240 000 km)
0 Drain, flush and refill cooling system (or every 60 mon .ths since last service,
whichever occurs first)."'See "Engine Coolant"
in the Index for what to use.
DATE
DATE
MILEAGE
ACTUAL SERVICED BY
Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure test I I
the cooling system and pressure cap.
An Emission Corztrol Service.
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Part C: Periodic Maintenance
Inspections
Listed below are inspections and services which should
be performed at least twice
a year (for instance, each
spring and fall).
You should let your dealer S service
department
or other qualified service center do these
jobs. Make sure any necessary repairs are completed
at once.
Proper procedures to perform these services may be
found in
a service manual. See “Service and Owner
Publications” in the Index.
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines and hoses for proper hook-up, binding, leaks,
cracks, chafing, etc. Clean and then inspect the drive
axle boot seals for damage, tears or leakage. Replace
seals if necessary.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system.
Look for broken, damaged,
missing or out-of-position parts
as well as open seams,
holes, loose connections or other conditions which could
cause a heat build-up in the floor pan or could let
exhaust fumes into the vehicle. See “Engine Exhaust’’ in
the Index.
Engine Cooling System Inspection
Inspect the hoses and have them replaced if they are
cracked, swollen or deteriorated. Inspect all pipes,
fittings
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.
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