1993 GMC SIERRA cooling

Right Button
Defrost (Top): Press here to operate the defroster. Heated air comes out
near the windshield. You can use it to help clear fog or ice on your
windshield.
Heater (Bottom): Press here, and heated air comes out near the floor. This
setting is best for passenger comfort in cold weather.
The air flow can be blended between the two positions. To blend between
positions, press the side of the button showing the area where you would like
more air flow. The system will automatically begin to blend toward the position
chosen. To stop the system between positions, just press the
SAME side of
the button again.
Left Button
Vent (Top): Press the top of this button and all of the airflow will come
through the instrument panel vents.
Heater (Bottom): Press the bottom of this button and all of the airflow will
come through the floor outlet.
The air flow can be blended between the two positions.
To blend between
positions, press the side
of the switch showing the area where you would like
more air flow. The system will automatically begin to blend toward the position
chosen. To stop the system between positions, just press the
SAME side of
the button again.
Temperature Selector Bar
The bar under your system display lets you select the temperat\
ure of the air
coming into your vehicle. Press
COLD for cooler air and press HOT for
warmer air. Release the bar when the system reaches the temperature you
want. The temperature is shown on the display by an arrow moving between
C and H.
Fan Control Button
This button is in the upper right corner of your system control panel. The fan
has four settings-low, medium
low, medium high and high. Press the top of
the button
(t) to increase the air flow. Press the bottom of the button (-) to
decrease the air flow. The setting you select is shown on your display as
LOW, MED LOW, MED HI or HI.
Air Recirculation Button
If you press the MAX button (RECIR on some models), the air in your
vehicle will be recirculated. With the air conditioner on,
MAX will give you
maximum cooling. It can also be used in all modes to help keep dust out of
your vehicle. When
MAX is selected, REC will light on your display.
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Your Driving and the Road
After Off-Road Driving
Remove any brush or debris that has collected on the underbody\
, chassis, or
under the hood. These accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings cleaned\
and checked. These substances can cause glazing and uneven braking. Check th\
e body
structure, steering, suspension, wheels, tires, and exhaust syste\
m for damage.
Also, check the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service due
to off-road use. Refer to
Section
7 for additional information.
Driving at Night
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Night driving is more dangerous than day driving. One reason is that some
drivers are likely
to be impaired-by alcohol or drugs, with night vision
problems, or by fatigue.
Here are some tips on night driving.
Drive defensively. Remember, this is the most dangerous time.
Don’t drink and drive (See “Drunken Driving” in the Index for more on
this problem).
Adjust your inside rear view mirror to reduce the glare from headlights
Since you can’t see as well, you may need to slow down and keep
behind
you.
more space between you and other vehicles. It’s hard
to tell how fast
the vehicle ahead is going just
by looking at its taillights.
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As in any driving situation, keep pace with traffic and allow adequat\
e
following distances.
Hill and Mountain Roads
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Driving on steep hills or mountains is different from driving in flat or rolling
terrain.
If you drive regularly in steep country, or if you’re planning to visit
there, here are some tips that can make your trips safer and \
more enjoyable.
(See “Off-Road” in the Index for information about driving off-road.)
Keep your vehicle in good shape. Check all fluid levels and also the
brakes, tires, cooling system and transmission. These parts can \
work
hard on mountain roads.
Know how to go down hills. The most important thing to know is this: let
your engine do some
of the slowing down. Don’t make your brakes do it
all. Shift to a lower gear when you go down a steep or long hill. That
way, you will slow down without excessive use of your brakes.
If you don’t shift down,’ your brakes could get so hot that they
- b wouldn’t work well. You would then have poor braking or even none
going
down a hill. You could crash. .Shift down to let your engine
assist your brakes on a steep downhill slope. I I
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CAUTION
It can be dangerous to get out of your vehicle if the shift lever is not
fully in
P (Park) with the parking brake firmly set. Your vehicle can
roll.
If you have left the engine running, the vehicle can move suddenl\
y.
You
or others could be injured. To be sure your vehicle won’t move,
when you’re on fairly level ground, use the steps that follow.
If you have four-wheel drive and your transfer case is in N (Neutral),
your vehicle will be free to
roll, even if your shift lever is in P (Park).
So, be sure the transfer case is in a drive gear-not in N (Neutral).
If you are parking on a hill, or if you’re pulling a trailer, also see
“Parking On Hills” in the Index.
When You Are Ready to Leave After Parklng on a Hill
1. Apply your regular brakes and hold the pedal down while you:
Start your engine;
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer To wing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are esp\
ecially
important in trailer operation are automatic transmission fluid (don’t overfill),
engine oil, axle lubricant, belts, cooling system, and brake ad\
justment. Each
of these is covered in this manual, and the Index will help \
you find them
quickly.
If you’re trailering, it’s a good idea to review these sections before
you start your trip.
Check periodically
to see that all hitch nuts and bolts are tight.
mailer Wiring Harness
See “Trailer Wiring Harness’’ in the Index.
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Cooling System
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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
CAUTION
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An electric fan under the hood can start up even when the engine\
is
not running and can injure you. Keep hands, clothing, and tool\
s
away from any electric fan.
m
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 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 cou
lose all coolant. That could cause an engine fire, and you could be
burned. Get any leak fixed before you drive the vehicle.
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NOTICE
Engine damage from running your engine without coolant isn’t covered by
I your warranty.
If there seems to be no leak, check to see if the electric engine fan (if you
have one) is running.
If the engine is overheating, the fan should be running.
If it isn’t, your vehicle needs service.
Start the engine again to see
if the regular fan runs when the engine does.
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
COLD, add a 50hO mixture of clean water (preferably distilled) and a proper
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antifreeze at the coolant recovery tank. (See “Coolant” in the Index for more
information about the proper coolant mix.)
* 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
for the proper coolant mix. 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
7 50/50 mix of clean water and a proper antifreeze.
I ln cold weather, water can freeze and crack the engine, radiator, heate\
r
:ore and other parts. Use the recommended coolant.
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I * You can be burned if you spill coolant on hot engine parts. CoolQni
A contains ethylene glycol and it will burn if the engine parts are hut
enough. Don’t spill coolant on a hot engine.
When the coolant in the coolant recovery is at
or above COLD, start your
vehicle.
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If the overheat warning continues, there’s one more thing you c\
an try. You
can add the proper coolant mix directly to the radiator, but \
be sure the radiator is cool before you
do it.
‘ Steam and scalding liquids from a hot cooling system can blow \
out
I- 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 t\
he 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 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.
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