1994 GMC SIERRA coolant

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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I 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.
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.
Adding Coolant -Gas Engines
To Check Coolant
The coolant recovery
tank
is located on the
passenger side at the
rear corner
of the
engine compartment.
When your engine
is cold, the coolant level should be at COLD, or a little
higher. When
your engine is warm, the level should be up to HOT, or a little
higher.
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To Add Coolant
If you need more coolant, add the proper mix at the coolant recovery tunk.
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 mix at the recovery tank, but be careful not to spill it.
A CAUTION:
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.
Adding Coolant -Diesel Engines
The coolant surge tank
is located on the
passenger side at the
rear corner
of the
engine compartment.
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To Check Coolant
When your engine is cold, the coolant level should be at the COLD mark,
or a little higher. When your engine is warm, the level should be above the
COLD mark.
If this light comes on,
it means you’re low
on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix at the surge tnnk, but only
when the engine is cool.
Open the air bleed valve on the thermostat housing to allow trapped air
out
of the system. Close the bleed valve when coolant begins to flow out.
I A CAUTION:
nrning the surge tank pressure cap when the engine and
radiator are hot can allow steam and scalding liquids to blow
out:
and burn you badly. Never turn the surge tank pressure cap -
even a little - when the engine and radiator are hot.
A CAUTION:
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.
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Radiator Pressure Cap-Gas Engines
The radiator pressure
cap must be tightly
installed with the
arrows
on the cap
lined
up with the
overflow tube
on the
radiator filler neck.
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.
Surge Tank Pressure Cap- Diesel Engines
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NOTICE:
Your surge tank pressure cap is a unique 15 psi (105 kPa)
pressure-type cap for use with surge tank cooling systems only.
It 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 top tube
of the coolant surge tank.
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.
When
you replace your thermostat, an AC" thermostat is recommended.
Power Steering Fluid
NOTICE:
Always turn the engine off before checking or adding power
steering fluid. The power steering pump cap is close to the fan
and other moving parts.
How To Check Power Steering Fluid
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.
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