1996 GMC SIERRA cooling

ANTI -
LOCK
Qnti-Lock Brake System Warning Light
With the anti-lock brake.
system, this light will come
on when
you start your
engine and may stay on
for several seconds.
That’s normal.
If the light stays on, or comes on when you’re driving,
your vehicle needs service.
If the regular brake system
warning light isn’t on,
you still have brakes, but you
don’t have anti-lock brakes.
If the regular brake system
warning light is also on, you don’t have anti-lock brakes
and there’s
a problem with your regular brakes. See
“Brake System Warning Light” earlier
in this part.
The anti-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn’t come on then, have it fixed so it will be
ready to warn
you if there is a problem.
Engine Coolant Temperature Gage
I This gage shows the engine
~ coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F
(100°C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the 260°F ( 125 “C) mark. If the
gage reaches the 260°F
(I 25 “C) mark, it indicates that
the cooling system is working beyond its capacity.
In “Problems
on the Road,” this manual shows what to
do. See “Engine Overheating” in the Index.
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The A/C button, between the temperature and mode
knobs, allows
the air coming into your vehicle to be
cooled. This setting
is useful for normal cooling on hot
days. When
you use A/C with the recirculation button
pushed
in, turn off recirculation as soon as the vehicle
reaches a comfortable interior temperature.
With the
A/C on, move the temperature knob to MAX
for maximum cooling.
This setting also puts the system
in the recirculation mode and helps
to maximize your air
conditioner’s performance and your vehicle’s fuel
economy. This setting also cools the air the fastest. After
the vehicle’s interior reaches a comfortable temperature,
move the temperature knob clockwise to place the air
conditioning system
in the normal mode.
Heating
The heater works best if you keep your windows closed
while using
it. On cold days, use the HEATER or
VENT/HEAT setting with the temperature knob in the
red area.
If you use the engine coolant heater before starting your
engine (in cold weather (20°F (-8°C) or lower), your
heating system
will produce warmer air faster, to heat
the passenger compartment
in cold weather. 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.
Ventilation System
For mild outside temperature when little heating or
cooling
is needed, use VENT to direct outside air
through
your vehicle. Air will flow through the
instrument panel outlets.
Your vehicle’s ventilation systeril supplies outside air
to the inside of your vehicle when it is moving. With
the side windows closed, air will flow into the front
air inlet grilles, through the vehicle, and out the air
exhaust valves.
Outside air will
also enter the vehicle when the heater or
the air conditioning fan is running, unless you have
the
recirculation button pushed in. For more information on
the recirculation button, see “Air Conditioning” earlier
in this section.
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Dr g at I
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 the body structure,
steering, suspension, wheels, tires and exhaust system
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 the Maintenance Schedule for
additional information.
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.
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0 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. Shift
to a lower gear when you go
down a steep or long hill.
If you don’t shift down, your brakes could get
so
hot that they 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.
0
0
0
0
~h CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition
off is dangerous. Your brakes will have to
do
all the work of slowing down. They could get so
hot that they wouldn’t work well. You would then
have poor braking
or even none going down a hill.
You could crash. Always have your engine running
and your vehicle in gear when you go downhill.
Know
how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your engine
and transmission, and
you can climb the hill better.
Stay
in your own lane when driving on two-lane
roads
in hills or mountains. Don’t swing wide or cut
across the center
of the road. Drive at speeds that let
you stay
in your own lane.
As you go over the top of a hill, be alert. There
could be something
in your lane, like a stalled car
or an accident.
You may see highway signs on mountains that warn of
special problems. Examples are long grades, passing or
no-passing zones, a falling rocks area’or winding
roads. Be alert to these and take appropriate action.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while
you:
0 Start your engine;
Shift into a gear; and
0 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 Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things
that are especially important in trailer
operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system
and brake adjustment. 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.
Trailer Wiring Harness
A seven-wire harness is stored under the rear end of
your vehicle. between the frame rails. An electrical
connector
will need to be installed at the trailer end of
the harness, by a qualified electrical technician. For
additional trailer wiring and towing information please
consult your
GM dealer. Securely attach the harness to
the trailer, then tape or strap it to your vehicle’s frame
rail.
Be sure you leave it loose enough so the wiring
won’t bind or break when turning with the trailer, but
not so loose that it drags on the ground. Store the
harness in its original position. Wrap the harness
together and tie
it neatly so it won’t be damaged. If you
tow a trailer, your Center High-Mounted Stoplamp
(CHMSL) may not be properly visible from behind.
You should select a trailer with
a CHMSL on it or, if
one is not available, have one installed. See your GM
dealer about how to connect your vehicle’s wiring to
a trailer CHMSL.
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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 Tdnk
B. Radiator Pressure Cap
C. Engine Fan(s)
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.
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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.
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:
I
I
I
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 SO/SO mixture
of ciecu? wter (preferably distilled) and DEX-COOL”
(orange-colored, silicate-free) antifreeze at the coolant
recovery tank.
(See (‘Engine Coolant” in the Index for
more information.)
I A CAUTION:
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. 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 TM antifreeze.
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 mix.
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