GMC SIERRA 1997 Owners Manual

Rear Towing
I NOTICE:
If your vehicle is equipped with a manual or
electric shift transfer
case, a towing dolly must be
used under the front wheels or vehicldpowertrain
damage
will occur.
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.
Engine Overheating (Gasoline Engine)
You will find a coolant temperature gage on your
vehicle’s instrument panel.
If your vehicle has a diesel engine, see “Engine
Overheating” in the Diesel Engine Supplement.
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If Steam Is Coming From Your Engine
I 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 you
open the hood.
CAUTION: (Continued) tin
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.
I 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.
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.
0 Tow a trailer. See “Driving on Grades” in the Index.
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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 (@)
for automatic transmissions.
If you no longer have
the overheat warning, you can
drive. Just
to be safe, drive slower for about 10 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 oflthe
engine and get everyone out
of the vehicle until it
cools down.
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. Radiator Pressure Cap
C. Engine Fan(s)
You may decide
not to lift the hood but to get service
help right away.
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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 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.
I
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.
I NOTICE:
Engine damage from running your engine
without coolant isn’t covered
by your warranty.
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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 -- Gasoline Engines
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 DEX-COOL@
(silicate-free) antifreeze at the coolant recovery tank. (See
“Engine Coolant’’
in the Index for more information.)
I
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix
will. Your vehicle’s coolant warning
system is set for the proper coolant mix.
CAUTION: (Continued) With plain water
or the wrong mix, your engine
could get too hot but you wouldn’t get the
overheat warning. Your engine could catch fire
and you or others could be burned. Use a
50/50
mix of clean water and DEX-COOL@coolant.
I NOTICE:
r
~~
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mix.
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I 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.
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
cool before
you do it.
is
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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 cooling 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
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 counterclockwise until it
first stops. (Don’t press down while turning the
pressure cap.)
2. Then keep turning the pressure cap, but now push
down as
you turn it. Remove the pressure cap.
If you hear a hiss, wait for that to stop.
A hiss means
there is still some pressure left.
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..
3. Fill the radiator with the proper DEX-COOL@
coolant mixture, up to the base of the filler neck.
4. Then fill the coolant recovery tank to the COLD mark.
5. Put the cap back on the coolant recovery tank, but
leave
the radiator pressure cap off.
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6. Start the engine and let it run until you can feel the 1
' upper radiator hose getting hot. Watch out for the
engine fan(s).
I 7. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more
of the proper DEX-COOL@ coolant mixture
through the filler neck until the level reaches the
base
of the filler neck.
f:
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to
flow out of the
filler neck, reinstall the pressure cap. Be sure the
arrows on the pressure cap line up like this.
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