1995 GMC SIERRA overheating

Table of Contents
Introduction - How to Use this Manual
This section tells you how to use your manual and includes safety
and vehicle damage warnings and symbols.
Section 1 - Seats and Restraint Systems
This section tells you how to use your seats and safety belts
properly.
It also explains the air ba, 0 s -y stem.
Section 2 - Features & Controls
This section explains how to start and operate your vehicle.
Section 3 - Comfort Controls & Audio Systems
This section tells you how to adjust the ventilation and comfort
controls and how to operate your audio system.
Section 4 - Your Driving and the Road
Here you’ll find helpful information and tips about the road and
how to drive under different conditions.
Section 5 - Problems on the Road
This section tells you what to do if you have a problem while
driving, such
as a flat tire or engine overheating. etc.
Section 6 - Service & Appearance Care
Here the manual tells you how to keep your vehicle running
properly and looking good.
Section 7 - Maintenance Schedule
This section tells you when to perform vehicle maintenance and
what fluids and lubricants to use.
Section 8 - Customer Assistance Information
L get service publications. It also gives you information on
This
section tells you how to contact
GM for assistance and how to
“Reporting Safety Defects” on page
8-4.
Index
Here’s an alphabetical listing of almost every subject in this
manual. You can use
it to quickly find something you want to read.
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Listed are four situations you may experience with your f~~el gage:
At the gas station. the fuel pump shuts off before the gage reads full.
It lakes a little more or less fuel to fill up than the fuel gage indicated.
For example, the gage may have indicated the tank was half
full, but it
actually took a little more or less than half the tank's capacity to fill the
, tank.
The gage moves a little when you turn a corner or speed up.
The gage doesn't go back to empty when you turn off the ignition.
None of these indicate
a problem with the fuel gage.
For information on how to fill your fuel tank, see "Fuel - Filling Your
Tank"
in the Index.
For your fuel tank capacity, see "Fuel -Tank Capacity" in the Index.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. Most of the time. the gage
pointer
will show your coolant temperature at 2 10°F (99"C), or less. But, if
you are pulling a heavy load or driving LIP hills, your coolant temperature
may rise and
fall near the red 260°F ( 128°C) mark. This is normal. If the
gage pointer moves to the red 260°F
(128°C) mark, your engine is too hot!
It means that your engine coolant has overheated. You should pull off the
road,
stop your vehicle. and turn off the engine as soon as possible.
Hot Coolant Can Burn You Badly!
In "Problems on the Road," this manual shows what to do. See "Engine
Overheating"
in thc Index.
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Making Turns
I NOTICE:
Making very sharp turns while trailering could cause the traile\
r to come in contact with the vehicle. Your vehicle could be
damaged. Avoid making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than normal. Do this
so your trailer won’t strike soft shoulders, curbs, road signs, trees, or other
objects. Avoid jerky or sudden maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra wiring (included in
the optional trailering package). 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 before 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 kmh) to reduce the possibility of engine and transmission overheating.
If you have an automatic transmission
you should use DRIVE (3) (or, as
you need to, a lower gear) when towing a trailer. Operating your vehicle in
DRIVE (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).
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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 (Pj (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.
Parking on Hills
You really should not park your vehicle, with a trailer attached, on a hill. If
something goes wrong, your rig could start to move. People can be injured,
and both your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here’s how to do it:
1.
2.
3.
4.
5.
6.
Apply your regular brakes, but don’t shift into PARK (P) yet, or in gear
for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the regular brakes until the
chocks absorb the load.
Re-apply the regular brakes. Then apply your parking brake, and then
shift
to PARK (P), or REVERSE (Rj for a manual transmission.
If you have
a four-wheel-drive vehicle, be sure the transfer case is in a
drive gear-not in NEUTRAL
(N).
Release the regular brakes.
A CAUTION:
It can be dangerous to get out of your vehicle if the shift lever is
not fully in
PARK (P) with the parking brake firmly set. Your
vehicle can rofl.
If you have Ieft the engine running, the vehicle can move
suddenly. You or others could be injured.
To be sure your vehicle
won’t move, even when you’re on fairly level ground, use the
steps that follow.
If you have four-wheel drive and your transfer case is in
NEUTRAL (N), your vehicle will be free to roll, even if your
shift lever is in
PARK (P). So, be sure the transfer case is in a
drive gear
- not in NEUTRAL (N).
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Engine Overheating
YOU will find a coolant temperature gage on your vehicle instrument panel.
If
YOU have a diesel engine, you will also find a low coolant light on your
instrument panel.
lf 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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NOTICE:
If there is water in your diesel fuel and the weather is warm or
humid, fungus and bacteria can grow in the fuel. They can
damage your fuel system. You'll need a diesel fuel biocide to
sterilize your fuel system. Your dealer can advise
you if you ever
need this.
If your fuel tank needs to be purged to remove water, see your
dealer or a qualified technician. Improper purging can damage
your fuel system.
Running Out of Fuel (Diesel Engines)
If the engine stalls and you think that you've run out of fuel, do this:
First, open the fuel filter air bleed valve.
Briefly crank the
engine and have
someone watch the
bleed valve. If there is
air, then you are
probably
out of fuel.
To restart your engine:
I. If you're parked on a level surface, add at least two gallons of fuel.
However, if you're parked
on a slope, you may need to add up to five
gallons of fuel.
2. With the air bleed valve open, turn your ignition key to START for 10
to
15 seconds to crank (but not start) your engine. Wait one minute
between intervals
of cranking to allow the starter motor to cool.
Overheating the starter motor could damage it. Keep doing this until
you can just see some clear fuel at the air bleed valve. (If, during this
step, the engine starts, turn the ignition off and close the valve before
restart.)
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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
( 12 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 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.
The proper coolant for your vehicle will:
Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 262°F (128°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning gages work as they should.
What to Use
Use a mixture of one-half cleun water (preferably distilled) and one-half
antifreeze that meets “GM Specification 6038-M,” which won’t damage
aluminum parts.
You can also use a recycled coolant conforming to “GM
Specification 6038-M.” Use GM Coolant Supplement (Sealer) with a
complete coolant flush and refill. If you use this mixture. you don’t need to
add anything else.
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
a proper antifreeze.
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To Check Coolant
A CAUTION:
Turning the surge tank pressure cap when the engine and
radiator are hot can allow steam and scalding liquids to blow out
and burn you badly. Never turn the surge tank pressure cap
-
even a little - when the engine and radiator are hot.
When your engine is cold, the coolant level should be at the COLD mark, or
a little higher.
If this light comes on, it means you’re low on engine coolant.
To Add Coolant
If you need more coolant, add the proper mix ut the surge tmk, but only
when the engine is cool. If the surge tank is empty, see “Engine
Overheating”
in the Index for the proper fill procedure.
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 replacing the pressure cap, make sure it is tight.
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