1994 GMC SIERRA engine coolant

A CAUTION:
If your vehicle has air conditioning, the auxiliary electric fa\
n
under the hood can start up even when the engine
is not running
and can injure you. Keep hands, clothing and tools away
from
any underhood electric fan.
If the coolant inside the coolant surge tank is boiling, don’t do anything else
until it cools down.
E The coolant level
should be slightly
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.
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I NOTICE:
Engine damage from running your engine without coolant isn’t \
covered
by your warranty.
If there seems to be no leak, start the engine 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.
How to Add Coolant to the Coolant Surge lank
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, radiator, \
heater
core and other parts. So use the recommended coolant.
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3. Open the air
bleed valve
located on the
thermostat
housing.
4. Fill the coolant
surge tank with
the proper mix,
up to the
COLD
mark.
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).
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Service & Appearance Care
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)
...................................... 6-4
Diesel Fuel Requirements and Fuel System
...................... 6-5
Checking Things Under the Hood
............................. 6-15
HoodRelease
.......................................... 6-15
Cleaning Your Diesel Engine
.............................. 6-16
Noise Control System .................................... 6-16
Engine Oil (Except Diesel)
................................ 6-17
Engine Oil (Diesel Engines)
............................... 6-24
iri
Air Cleaner ............................................ 6-29
Automatic Fluid ........................................ 6-30
ManualFluid
........................................... 6-33
Hydraulic Clutch
........................................ 6-34
RearAxle ............................................. 6-35
mnsfer Case
.......................................... 6-36
FrontAxle
............................................. 6-37
Engine Coolant
......................................... 6-38
Power Steering Fluid
.................................... 6-43
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Things that burn can get on hot engine parts and start a fire.
These include liquids like gasoline or diesel fuel, oil, coolant,
brake fluid, windshield washer and other fluids, and plastic or
rubber. You or others could be burned. Be careful not to drop or
I spill things that will burn onto a hot engine.
Before closing the hood, be sure all filler caps are on properly. Pull down
the hood and close it firmly.
Cleaning Your Diesel Engine
NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm or hot, or when it is running,
you could cause
serious damage to it.
If you ever clean the engine, clean it only
when it is cold.
Noise Control System
The following information relates to compliance with Federal noise
emission standards for vehicles
with a Gross Vehicle Weight Rating
(GVWR) of more than
10,000 pounds (4 536 kilograms). The Maintenance
Schedule booklet provides information on maintaining the noise control
system to minimize degradation
of the noise emission control system during
the life of your vehicle. The noise control system warranty
is given in your
Warranty hooklet.
These standards apply only to vehicles sold
in the United States.
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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).
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
delivery, or
in stop-and-go traffic).
You tow a trailer often.
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
and-filter 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 (- 18°C) or colder. If your vehicle has this option,
see “Engine Coolant Heater
” in the Index.
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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 OF (-29”C), or -34°F (-37°C) in
Canada and for vehicles with the cold climate option.
Give boiling protection up to 258 OF ( 125 O C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
What to Use
Use a mixture of one-half clean wuter (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.
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