1996 GMC SIERRA coolant temperature

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Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the wrong
kind of extension cord could overheat and cause
a fire.
You could be seriously injured. Plug the
cord into a properly grounded three-prong 110-volt
AC outlet. If the cord won't reach, use a
heavy-duty three-prong extension cord rated for
at least
15 amps.
3. After you've used the coolant heater, be sure to
store
the cord as it was before to keep it away
from moving engine parts.
If you don't. it could
be damaged.
How long should you keep the coolant heater plugged
in'? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your GM dealer in the area where you'll be parking your
vehicle. The dea1e.r can give
you the best advice for that
particular area.
Automatic Transmission Operation
There are several different positions for your- shift lever.
If your vehicle is equipped with an automatic
transmission,
it now features an electronic shift position
indicator
within the instrument cluster. This display
must be powered anytime the shift lever is capable
of
being moved out of the PARK (P) position. This means
that
if your key is in the OFF position, rather than the
LOCK position, there will be a small current drain on
your battery which could discharge your battery over
a period of time. If you have to leave your key in the
ignition
in the OFF position for an extended period, it is
recommended that you disconnect the battery cable from
the battery
to prevent discharging your battery.
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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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Daytime Running Lamps Indicator Light Check Gages Light
This light goes on whenever
the DRL are on.
CHECK
GAGES
This light will come on
briefly when you are
starting
the engine.
When
it begins to get dark, the DRL indicator light is a
reminder to turn
on your headlamps.
If the light comes on and stays on w.hile you are driving,
it could indicate a problem with your vehicle. It could be
a problem with your oil pressure, coolant temperature,
or some other problem. Check your various gages to see
if they are in the warning zones. If they are, have your
vehicle serviced right away.
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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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Turn Signals When Towing a Trailer
The green arrows on your instrument panel will flash
whenever
you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the green arrows
on your
instrument panel will flash for turns even
if the bulbs on
the trailer are burned out. Thus, you may
think drivers
behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are
still working.
Driving On Grades
Reduce speed and shift to a lower gear be~m you start
down
a long or steep downgrade. If you don’t shift
down,
you might have to use your brakes so much that
they would get hot and
no longer work well.
On a long uphill grade,
shift down and reduce your
speed
to around 45 mph (70 km/h) to reduce the
possibility
of engine and transmission overheating.
If you have an automatic transmission, you should use
THIRD
(3) (or, as you need to, a lower gear) when
towing a trailer. Operating your vehicle in THIRD
(3)
when towing a trailer will minimize heat build-up and
extend
the life of your transmission
If
you have a manual transmission and you are towing a
trailer,
it’s better not to use FIFTH (5) gear. Just drive in
FOURTH (4) gear (or, as you need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If
you turn
your engine off‘ immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar
to engine overheating. To avoid this, let the
engine
run while parked (preferably on level ground)
with the automatic transmission
in PARK (P) (or the
manual transmission out
of gear and the parking brake
applied) for a few minutes before turning
the engine off.
If you do get the overheat warning, see “Engine
Overheating’’
in the Index.
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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.
If 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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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often
to check the lubricant and when to change it. See
"Scheduled Maintenance Services"
in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole.
you'll
need to add some lubricant.
If the differential is at operating temperature (warm),
add enough lubricant
to raise the level to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant to raise
the level
to 1/2 inch (1 2 mm) below the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind
of lubricant to use. See "Recommended Fluids and
Lubricants"
in the Index.
Engine Coolant
The cooling system in your vehicle is filled with new
DEX-COOL
TM (orange-colored, silicate-free) engine
coolant. This coolant is designed
to remain in your
vehicle for
5 years or 100,000 miles (1 66 000 km),
whichever occurs first.
The following explains
your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see "Engine Overheating"
in
the Index.
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A 50/50 mixture of water and the proper coolant for
your vehicle
will:
Give freezing prorecrlon down to -34°F (-37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning gages work as they should.
NOTICE:
When adding coolant it is important that you use
DEX-COOL TM (orange-colored, silicate-free)
coolant meeting
GM Specification 6277M.
If silicated coolant is added to the system,
premature engine, heater core or radiator
corrosion may result.
In addition, the engine
coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. use
a mixture
of one-half dum wwter (preferably
distilled) and one-half
DEX-COOL” (orange-colored.
silicate-free) antifreeze that meets
GM Specification
6277M. which
won‘t damage aluminum parts. Use
GM Engine Coolant Supplement (sealer) (GM Part
No. 363462 1 ) with any complete coolant change. If you
use this mixture.
you don’t need to add anything else.
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
50150 mix of clean
water and
DEX-COOL TM (orange-colored,
silicate-free) antifreeze.
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