1993 GMC SIERRA engine overheat

Your Driving and the Road
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 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
45 mph (70
kmlh) or less to reduce the possibility of engine and transmission overheating.
IT you have an automatic transmission, you should use D (or, as you need to,
a lower gear) when towing a trailer. Operating your vehicle i\
n
D when towing
a trailer will minimize heat buildup and extend the life of your transmission.
Or, if you have a manual transmission with fifth gear and you are towing a
trailer, it’s better not to use fifth gear. Just drive in fourth gear
(or, as you
need to, a lower gear).
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. Apply your regular brakes, but don’t shift into P (Park) yet, or into gear
2. Have someone place chocks under the trailer wheels.
for a manual transmission.
3. When the wheel chocks are
in place, release the regular brakes until the
chocks absorb the load.
4. Reapply the regular brakes. Then apply your parking brake, and \
then
5. If you have a four-wheel-drive vehicle, be sure the transfer case is in a
6. Release the regular brakes.
shift
to
P (Park), or R (Reverse) for a manual transmission.
drive gear-not in
N (Neutral).
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Pmb/ems on the Road
1 Section
Here you’ll find what to do about some problems that can occur on the road .
Hazard Warning Flasher ........................................................................\
............... 5-2
Other Warning Devices ........................................................................\
................. 5-3
Jump Starting ........................................................................\
................................ 5-3
Towing Your Vehicle ........................................................................\
...................... 5-8
Engine Overheating ........................................................................\
....................... 5-9
If
If
a Tire Goes Flat ........................................................................\
...................... 5-17
Changing a Flat Tire
........................................................................\
............... 5-17
Jack Storage
........................................................................\
............................ 5-19
Spare Tire
........................................................................\
................................ 5-20
You’re Stuck: In Sand. Mud. Ice or Snow ................................................... 5-33
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If your vehicle has the four-wheel-drive option and the transfer c\
ase is
engaged, a dolly must be used under the rear wheels when towi\
ng from the
front.
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.
If Steam Is Coming From Your Engine:
K2509
I CAUTION
A
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.
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Problems on the Road
If your engine catches fire because you keep driving with no cool\
ant, your
vehicle can be bac"lI damaged.
T- ! costly rep; 1 would not be Iverec
by your warranty.
If No Steam Is Coming From Your Engine:
If you get the overheat warning but see or hear no steam, th\
e problem may
not be too serious. Sometimes the engine can get a little too\
hot when you:
Climb a long hill on a hot day.
Stop after high speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of steam, try t\
his 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
3. If you're in a traffic jam, shift to N (Neutral).
window as necessary.
If you no longer have the overheat warning, you can drive. Just
to be safe,
drive slower for about ten minutes.
If the warning doesn't come back on, you
can drive normally.
If the warning continues, pull over, stop, and park your vehic\
le right away.
If there's still no sign of steam, push the accelerator until the engine speed is
about twice
as fast 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 OFF THE 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.
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I
I
‘4
!b P4
LL
1
PO593
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.
I I
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.
PO206
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 You’re Stuck: In Sand,
Mud,
Ice or Snow
What you don’t want to do when your vehicle is stuck is to spin your
wheels. The method known as “rocking” can help you get o\
ut when you’re
stuck, but you must use caution.
CAUTION - --
I * If you let your tires spin at high speed, they can explode and you or
,A others could be injured. And, the transmission or other parts of the
vehicle can overheat. That could cause an engine compartment fire
or other damage. When you’re stuck, spin the wheels as little as
possible. Don’t spin the wheels above
35 mph (55 krnlh) as shown
I on the speedometer.
;pinning your wheels can destroy parts of your vehicle as well as the
res.
If you spin the wheels too fast while shifting your transmission back
.nd forth, you can destroy your transmission.
NOTICE 1
Rocking your vehicle to get it out:
First, turn your steering wheel left and right. That will clear the area around
your front wheels. Then shift back and forth between
R and a forward gear
(or with a manual transmission, between First or Second gear and Reverse),
spinning the wheels as little as possible. Release the accelerator pedal while
you shift, and press lightly on the accelerator pedal when the transmission is
in gear.
If that doesn’t get you out after a few tries, you may need to be
towed out.
Or, you can use your recovery hooks, if your vehicle has them. If
you do need to be towed out, see “Towing Your Vehicle” in the Index.
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Service & Appearance ,Care
Engine Coolant
r
PO593
The following explains your cooling system and how to add cool\
ant 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).
Give boiling protection up to 258°F (125°C).
Protect against rust and corrosion:
Help keep the proper engine temperature.
Let the warning lights and gages work as thiy should.
What to Use:
Use a ,mixture of clean water (preferably distilled), and antifreeze that meets
“GM Specification 6038-M,” which won’t damage aluminum p\
arts.
Also use
GM Engine Coolant Supplement (sealer) with a complete coolant change. If
you use these, you don’t need to add anything else.
,
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