1998 GMC SIERRA Owners Manual

5. Put the transfer case in NEUTRAL (N). See
“Four-Wheel Drive’’
in the Index for the proper
procedure to select NEUTRAL
(N).
6. When the vehicle is hooked up. release the
parking brake.
7. Turn the ignition key to OFF.
Four- Wheel-Drive Vehicles (Electronic
Transfer Case)
Eml Limits -- 35 mph (55 km/JZ), 50 milc?s (80 kndh)
If your vehicle is four-wheel drive with an electronic
transfer case, use the following directions:
I. Engage the parking brake.
2. Turn the ignition key to ON.
3. Clamp the steering wheel in a straight-ahead position
with
a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
4. Put the transmission in NEUTRAL (N).
5. Put the transfer case in 2 High (2HI).
6. When the vehicle is hooked up, release the
parking brake.
7. Turn the ignition key to OFF.
NOTICE:
If your vehicle is equipped with four-wheel drive
and the towing limits must be exceeded, a towing
dolly must be used under the front wheels or
vehicle/powertrain damage will occur.
I 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. See “Engine Coolant
Temperature Gage”
in the Index.
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
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)
I
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.
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 fdst 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 ofthe
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.
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)
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If your vehicle has air conditioning, the auxiliary
electric engine cooling 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
codant 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.
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.
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If there seems to be no leak, start the engine again. See if
the engine cooling
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 C'IC~LIII r.tuter- (preferably distilled) and DEX-COOL@
engine coolant at the coolant recovery tank. (See
"Engine Coolant"
in the Index for more information.)
I A CAUTION: I
I CAUTION: (Continued)
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%oolant.
I NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts. Use the recommended coolant and the proper
coolant mixture.
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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
mixture directly to
the radiator, but be sure the cooling
system is cool before you do it.
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A CAUTION:
Steam and scalding liquids from a
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.
I
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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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