1994 GMC SIERRA coolant

Heater Output
Engine Coolant Heater (Engine Block Heater)
If your vehicle has a diesel engine, it is equipped with an engine coolant
heater. An engine coolant heater
is optional on gas engine vehicles. You can
use an engine coolant heater during initial start-up
in cold weather (20” F,
-8” C, or lower) to help heat the passenger compartment faster. Because an
engine coolant heater warms the engine coolant, your vehicle’s heating
system can provide some heat
as soon as you start the engine.
The
use of an engine coolant heater also reduces the time it takes for the
engine to reach normal operating temperature, and shortens the time it takes
the heater to reach full output. For more information, See “Engine Coolant
Heater”
in the Index.
Diesel Engine
If you idle your diesel engine for a long time when it’s cold outside, your
heater may blow out cool air. This
is normal. When you increase the engine
speed, your heater should blow
out warmer air. If it doesn’t, your coolant
level may be low. See “Engine Coolant”
in the Index to find out how to
check your coolant level.
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Winter Driving
Here are some tips for winter driving:
Have your Vehicle in good shape for winter. Be sure your engine
coolant mix
is correct.
0 You may want to put winter emergency supplies in your vehicle.
Include an ice scraper,
a small brush or broom, a supply of windshield
washer fluid, a rag, some winter outer clothing,
a small shovel, a flashlight,
a red cloth, and a couple of reflective warning triangles. And, if you will be
driving under severe conditions, include
a small bag of sand, a piece of old
carpet or
a couple of burlap bags to help provide traction. Be sure you
properly secure these items
in your vehicle.
Driving on Snow or Ice
Most of the time, those places where your tires meet the road probably have
good traction.
However,
if there is snow or ice between your tires and the road, you can
have a very slippery situation.
You’ll have a lot less traction or “grip” and
will need
to be very careful.
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Driving On Grades
Reduce speed and shift to a lower gear before you start down a long or
steep downgrade.
If you don’t shift down, you might have to use your
brakes
so much that they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your speed to around
45 mph
(70 km/h) to reduce the possibility of engine and transmission overheating.
When towing at high altitude with steep uphill grades,you need to consider
the following information. The lower atmospheric pressure at high altitude
allows your vehicles engine coolant to boil at a lower temperature than at
normal altitudes.
If you immediately turn your engine off after towing at high altitude with
steep uphill grades, your vehicle may show signs similar
to engine
overheating.
To avoid this, let your vehicle operate in a parked position with
the transmission in
“N” (Neutral) for a few minutes before you turn off the
engine. If you do get the overheat warning, see “Engine Overheating” in
the Index.
If you have an automatic transmission, you should use
“D” (or, as you need
to, a lower gear) when towing a trailer. Operating your vehicle in
“D” when
towing a trailer will minimize heat buildup and extend the life
of your
transmission.
If you have a manual transmission and
you are towing a trailer, it’s better
not to use fifth gear. Just drive in fourth gear (or, as you need to, a lower
gear).
Parking on Hills
You really should not park your vehicle, with a trailer attached, on a hill. If
something goes wrong, your rig could start
to move. People can be injured,
and both your vehicle and the trailer can be damaged.
But if you ever have to park your rig on a hill, here’s how
to do it:
1.
2.
3.
4.
5.
6.
Apply your regular brakes, but don’t shift into “P’ (Park) yet, or in gear
for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are in place, release the regular brakes until the
chocks absorb
the load.
Re-apply the regular brakes. Then apply your parking brake, and then
shift to
“P7, (Park), or “R” (Reverse) for a manual transmission.
If
you have a four-wheel-drive vehicle, be sure the transfer case is in a
drive gear-not in
“N7 (Neutral).
Release
the regular brakes.
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,ngine Overheating
You will find a coolant temperature gage on your vehicle instrument panel.
If you have a diesel engine, you will also find a low coolant light on your
instrument panel.
If Steam 1s Coming From Your Engine
NOTICE:
If your engine catches fire because you keep driving with no
coolant, your vehicle can be badly damaged. The costly repairs
would not be covered by your warranty.
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Cooling System -Gas Engines
When you decide it's
safe to lift the hood,
here's what you'll see:
A. Coolant recovery
tank
B. Engine fan(s)
C. Radiator pressure
cap
A CAUTION:
If your vehicle has air conditioning, the auxiliary electric fan
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 recovery 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.
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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 Recovery Tank
If you haven’t found a problem yet, but the coolant level isn’t at or above
the
COLD mark, add a 50/50 mixture of clean water (preferably distilled)
and
a proper antifreeze at the coolant recovery tank. (See “Engine Coolant’’
in the Index for more information about the proper coolant mix.)
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I NOTICE:
In cold weather, water can freeze and crack the engine, radiator, \
heater core and other parts. Use the recommended coolant.
When the coolant in the coolant recovery tank is at or above the COLD
mark, start your vehicle.
If the overheat warning continues, there’s one more thing you can try. You
can add the proper coolant mix directly to the radiator!, but be sure the
cooling system is cool before
you do it.
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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 to the left until it first stops. (Don’t press
down while turning the pressure cap.)
If you hear a hiss, wait for that
to stop. A hiss means there is still some
pressure left.
I
r
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