1994 CHEVROLET SUBURBAN engine coolant

If the coolant inside the coolant surge tank is boiling, don't do anything else
until it cools down.
The coolant level
should be at
or above
the
COLD mark. If it
isn't, you may have
a
leak in the radiator
hoses, heater hoses,
radiator, water
pump
or somewhere else in
the cooling system.
NOTICE:
Engine damage from running your engine without coolant isn't
covered by your warranty.
If there seems to be no leak, start the engifie again. See if the fan speed
increases when idle speed
is doubled by pushing the accelerator pedal down
If
it doesn't, your vehicle needs service. Turn off the engine.
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How to Add Coolant to the Coolant Surge Tank
If you haven’t found a problem yet, but the coolant level isn’t at the COLD
mark add a 50/50 mixture of clean water (preferably distilled) and a proper
antifreeze
at the coolant surge tank, but be sure the cooling system,
including the coolant surge tank pressure cap,
is cool before you do it. (See
“Engine Coolant”
in the Index for more information about the proper
coolant mix.)
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NOTICE:
In cold weather, water can freeze and crack the engine, radiat\
or,
heater core and other parts.
So use the recommended coolant.
1. You can remove the coolant surge tank pressure cap when the cooling
system, including the coolant surge tank pressure cap and upper
radiator
hose, is no longer hot.
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While filling the surge tank, watch to see if coolant begins to stream out
the air bleed valve. When coolant begins to stream out, close the valve.
5. With the air bleed
valve closed and
the coolant surge
tank pressure cap
off, start the
engine and let
it
run until you can
feel
the upper
radiator hose
getting hot.
Watch out for the
engine fan(
s).
6. By this time, the coolant level inside the coolant surge tank may be
lower.
If the level is lower, add more of the proper mix to the coolant
surge tank until the level reaches the
COLD mark.
7. Then replace the
pressure cap.
Be
sure the arrows
on the pressure
cap line up like
this.
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Service & Appearance
I Section
Here you will find information about the care of your vehicle . This section
begins with service and fuel information. and then it shows how to check
important fluid and lubricant levels
. There is also technical information
about your vehicle. and a section devoted to its appearance care
.
Service ................................................... 6-3
Fuel (Gasoline Engines)
............................
Diesel Fuel Requirements and Fuel System ..........
Checking Things Under the Hood ........... .....
........ 6-4
.......... 6-5
......... 6-14
HoodRelease
.......................................... 6-14
Cleaning Your Diesel Engine
............................ 6-15
Engine Oil (Except Diesel)
................................ 6-16
Engine Oil (Diesel Engines)
............................... 6-22
Aircleaner
.................... .................. 6-27 ..
Automatic Transmission Fluid ............................. 6-28
Manual Transmission Fluid
............................... 6-31
Hydraulic Clutch
........................................ 6-32
RearAxle
............................................. 6-33
Transfer Case
.......................................... 6-34
FrontAxle
........................................... 6-35
Engine Coolant
......................................... 6-35
Power Steering Fluid
.............. .................. 640
Windshield Washer Fluid
............................... 6-42
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Engine Oil Additives
Don’t add anything to your oil. Your GM dealer is ready to advise if you
think something should be added.
When to Change Engine Oil
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
0 It’s below freezing outside and most trips are less than 10 miles (16 km).
The engine is at low speed most of the time (as in door-to-door
You tow a trailer often.
delivery,
or in stop-and-go traffic).
Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any one
of these is true for your vehicle, then you need to change your oil
andfifilter every 3,000 miles (5 000 km) or 3 months - whichever comes
first
.
Light Duty Emissions:
If none of them is true, change the oil every 7,500 miles (12 500 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that.
Heavy Duty Emissions:
If none of them is true, change the oil every 6,000 miles ( 10 000 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that if mileage determines when you
change your oil.
If time determines when you change your oil, change the
filter each time you change your
oil.
Engine Coolant Heater (Engine Block Heater)
An engine coolant heater can be a big help if you have to park outside in
very cold weather,
0°F (-1 8 “C) or colder. If your vehicle has this option,
see “Engine Coolant Heater
” in the Index.
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.)
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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how often to check the
lubricant and when to change
it. See “Scheduled Maintenance Services” in
the Index.
How to Check Lubricant
If the level is below
the bottom of the filler
plug hole, you’ll need
to add some lubricant.
If the differential is at
operating temperature
(warm), add enough
lubricant to raise the level
to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant to raise the level to
1/2 inch
(12 mm) below the filler plug hole.
What to use
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
Engine Coolant
The following explains your cooling system and how to add coolant when it
is low. If you have a problem with engine overheating, see “Engine
Overheating”
in the Index.
The proper coolant for your vehicle will:
Give freezing protection down to -20°F (-29”C), or -34°F (-37°C) in
Give boiling protection up to 258°F (1 25°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Canada
and for vehicles with the cold climate option.
Let the warning lights and gages work as they should.
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What to Use
use a mixture of one-half clean water (preferably distilled) and one-half
antifreeze that meets
“GM Specification 6038-M,” which won’t damage
aluminum
parts. You can also use a recycled coolant conforming to “GM
Specification 6038-M” with a complete coolant flush and refill. If you use
this mixture, you don’t need
to add anything else.
NOTICE:
If you use an improper coolant mix, your engine could overheat
and be badly damaged. The repair cost wouldn’t be covered by
your warranty.
TOO much water in the mix can freeze and crack
the engine, radiator, heater core and other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when the engine is cold
and follow the steps under “Adding Coolant” for
the proper way to add
coolant.
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.
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