1995 GMC SIERRA Owners Manual

lowing From the Rear
NOTICE:
Towing pickup models from the rear while loaded with heavy
cargo may cause the frame side rails to flex sufficiently
to allow
the pickup box to contact the cab and could cause damage to \
the
cab and/or box.
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Engine 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.
lf Steam Is Coming From Your Engine
A CAUTION:
Steam from an overheated engine can burn you badly, even if
you just open the hood. Stay away from the engine if you see or
hear steam coming from it. Just turn it
off and get everyone
away from the vehicle until it cools down. Wait until there is no
sign of steam or coolant before opening the hood.
If you keep driving when your engine is overheated, the liquids
in it can catch fire. You or others could be badly burned. Stop
your engine
if it overheats, and get out of the vehicle until the
engine
is cool.
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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If No Steam Is Coming From Your Engine
If you get the overheat warning but see or hear no steam, the problem may
not be too serious. Sometimes the engine can get a little too hot when you:
0 Climb a long hill on a hot day.
0 Stop after high speed driving.
0 Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades’’ in the Index.
If
you get the overheat warning with no sign of steam, try this for a minute
or
so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan speed and open the
window as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N); otherwise, shift to the
highest gear while driving
- AUTOMATIC OVERDRIVE (@) or
DRIVE
(3) for automatic transmissions.
If you no longer have the overheat warning, you can drive. Just to be safe,
drive slower for about ten minutes. If the warning doesn’t come back on,
you can drive normally.
If
the warning continues, pull over, stop, and park your vehicle right away.
If there’s still no sign of steam, push the accelerator until the engine speed is
about twice as fast as normal idle speed. Bring the engine speed back to
normal idle speed after two or three minutes. Now see
if the warning stops.
But then, if
you still have the warning, turn ofSthe engine and get everyone
out of the vehicle until it cools down.
You may decide not to lift the hood but to get service help right away.
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Cooling System - Gasoline 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
I A CAUTION:
If your vehicle has air conditioning, the auxiliary electric fan
under the hood can start up even when the engine is not runn\
ing
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.
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The coolant level
should be a1 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.
A CAUTION:
Heater and radiator hoses, and other engine parts, can be very
hot. Don’t touch them.
If you do, you can be burned.
Don’t run the engine
if there is a leak. If you run the engine, it
could lose all coolant. That could cause an engine fire, and you
could be burned. Get any leak fixed before you drive the vehicle.
NOTICE:
Engine damage from running your engine without coolant isn’t
covered
by your warranty.
If there seem 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 SO/SO mixture of c.lea12 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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NOTICE:
In cold weather, water can freeze and crack the engine, radiat\
or,
heater core and other parts. Use the recommended coolant.
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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.
A CAUTION:
Steam and scalding liquids from a hot cooling system can blow
out and burn you badly. They are under pressure, and if you
turn the radiator pressure cap
- even a little - they can come
out
at high speed. Never turn the cap when the cooling system,
including the radiator pressure cap, is hot. Wait for the cool\
ing
system and radiator pressure cap to cool if you ever have to turn
the pressure cap.
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How to Add Coolant to the Radiator
r
1.
I
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.
:_. .w 2. Then keep
turning the
pressure cap, but
now push down
as you turn it.
Remove the
pressure cap.
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