tow CHEVROLET SUBURBAN 1994 Service Manual

If No Steam Is Coming From Your Engine
If you get the overheat warning but see or hear no steam, the 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 this 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 vehicle 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.
Cooling System -Gas Engines
When you decide it’s
safe to lift the hood,
here’s what you’ll see:
A. Coolant recovery
“I tank
B. Engine fan(s)
C. Radiator pressure
cap
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster to provide more air to cool
the engine. In most every day
driving conditions the fan
is spinning slower and clutch is not fully engaged.
This improves
fuel economy and reduces fan noise. Under heavy vehicle
loading, trailer towing and/or high outside temperatures, the fan speed
increases as the clutch more fully engages.
So you may hear an increase in
fan noise. This is normal and should not be mistaken as the transmission
slipping or making extra shifts.
It is merely the cooling system functioning
properly. The
fan will slow down when additional cooling is not required
and the clutch partially disengages.
You may also hear this fan noise when you start the engine. It will go away
as the fan clutch partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving, especially if you
maintain your tires properly. If air goes out of a tire, it’s much more likely to
leak out slowly. But if you should ever have
a “blowout,” here are a few tips
about what to expect and what
to do:
If a front tire fails, the flat tire will create a drag that pulls the vehicle
toward that side. Take your foot off the accelerator pedal and grip the
steering wheel firmly. Steer to maintain lane position, then gently brake to a
stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a skid and may
require the same correction you’d use in a skid. In any rear blowout, remove
your foot from the accelerator pedal. Get the vehicle under control
by
steering the way you want the vehicle to go. It may be very bumpy and
noisy, but you can still steer. Gently brake to a stop, well off the road if
possible.
If a
tire goes flat, the next section shows how to use your jacking equipment
to change a flat tire safely.
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Front Position Rear Position
Replace the wheel
nuts with the rounded
end
of the nuts toward
the wheel.
Tighten each wheel
nut
by hand until the
wheel
is held against
the hub.
L
Lower the vehicle by rotating the ratchet to the left. Lower the jack
completely.
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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 out when you’re
stuck, but you must use caution.
NOTICE:
Spinning your wheels can destroy parts of your vehicle as well as
the tires. If you spin the wheels too fast while shifting your
transmission back and forth, you can destroy
your transmission.
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” (Reverse) 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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NOTICE:
Never use the recovery hooks to tow the vehicle. Your vehicle \
could be damaged and
it would not be covered by warranty.
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Engine Oil (Except Diesel)
It's a good idea to check your engine oil every time you get fuel. In order to
get an accurate reading, the oil must be warm and the vehicle must be on
level ground.
Turn
off the engine
and give the oil a few
minutes to drain
back r"' ' '
1 into the oil pan. If you
don't, the oil dipstick
might not show the
actual level.
To Check Engine Oil
I
Pull out the dipstick and clean it with a paper towel or cloth, then push it
back in all the way. Remove it again, keeping the tip lower.
When to Add Oil
If the oil is at or below the ADD mark, then you'll need to add some oil. But
you must use the right kind. This section explains what kind of oil to use.
For crankcase capacity,
see "Capacities and Specifications" in the Index.
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Engine Oil Additives
Don’t add anything to your oil. Your GM dealer is ready to advise if you
think something should be added.
When to Change Engine Oil
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
0 It’s below freezing outside and most trips are less than 10 miles (16 km).
The engine is at low speed most of the time (as in door-to-door
You tow a trailer often.
delivery,
or in stop-and-go traffic).
Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any one
of these is true for your vehicle, then you need to change your oil
andfifilter every 3,000 miles (5 000 km) or 3 months - whichever comes
first
.
Light Duty Emissions:
If none of them is true, change the oil every 7,500 miles (12 500 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that.
Heavy Duty Emissions:
If none of them is true, change the oil every 6,000 miles ( 10 000 km) or
12 months - whichever comes first. Change the filter at the first oil change
and at every other oil change after that if mileage determines when you
change your oil.
If time determines when you change your oil, change the
filter each time you change your
oil.
Engine Coolant Heater (Engine Block Heater)
An engine coolant heater can be a big help if you have to park outside in
very cold weather,
0°F (-1 8 “C) or colder. If your vehicle has this option,
see “Engine Coolant Heater
” in the Index.
What to Do with Used Oil
Did you know that used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer? Don’t let used oil stay
on your skin for very long. Clean your skin and nails with soap and water,
or
a good hand cleaner. Wash or properly throw away clothing or rags
containing
used engine oil. (See the manufacturer’s warnings about the use
and disposal of oil products.)
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Used oil can be a real threat to the environment. If you change your own oil,
be sure to drain all free-flowing oil from the filter before disposal. Don't ever
dispose of oil by putting it in the trash, pouring it on the ground, into sewers,
or into streams or bodies of water. Instead, recycle it by taking it to a place
that collects used oil. If you have a problem properly disposing of your used
oil, ask your dealer, a service station or a local recycling center for help.
Engine Oil (Diesel Engines)
It's a good idea to check your engine oil level every time you get fuel. In
order to get an accurate reading, the oil must be warm and the vehicle must
be on level ground.
A
Turn off the engine
and give the oil a few
minutes to drain back
into the oil pan. If you
don't, the oil dipstick
might not show the
actual level.
To Check Engine Oil
Pull out the dipstick and clean it with a paper towel or a cloth, then push it
back
in all the way. Remove it again, keeping the tip lower.
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This doughnut-shaped logo (symbol) is used on most oil containers to help
you select the correct oil.
You should look for this on the oil container, and use only those oils that
display the logo.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the
requirements for your vehicle.
Engine Oil Additives
Don’t add anything to your oil. Your GM dealer is ready to advise if you
think something should be added.
When to Change Engine Oil
See if any one of these is true for you:
Most trips are less than 4 miles (6 km).
0 It’s below freezing outside and most trips are less than 10 miles
0 The engine is at low speed most of the time (as in door-to-door
(16 km).
delivery,
or in stop-and-go traffic).
You tow a trailer often.
0 Most trips are through dusty places.
The vehicle is frequently operated off-road.
If any
of these is true for your vehicle, then you need to change your oil and
filter
every 2,500 miles (4 000 km) or 3 months - whichever comes first.
If none of them is true, change the oil and filter every 5,000 miles
(8 000 km) or 12 months - whichever comes first.
What to Do with Used Oil
Did you know that used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer? Don’t let used oil stay
on your
skin for very long. Clean your skin and nails with soap and water,
or
a good hand cleaner. Wash or properly throw away clothing or rags
containing used engine
oil. (See the manufacturer’s warnings about the use
and disposal
of oil products.)
Used oil can be a real threat to the environment.
If you change your own oil.
be sure to drain all free-flowing oil from the filter before disposal. Don’t
ever dispose of oil by putting
it in the trash, pouring it on the ground, into
sewers, or into streams
or bodies of water. Instead, recycle it by taking it to
a place that collects used oil. If you have a problem properly disposing of
your used oil,
ask your dealer, a service station or a local recycling center
for help.
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To remove the air
cleaner filter
on a gas
engine or
a 6.5 liter
naturally aspirated
diesel, turn the wing
nuts
to the left.
Remove the cover and
change the filter.
To remove the air cleaner filter on a 6.5 liter turbocharged diesel, first
remove the rubber elbow. Remember to observe the caution about
turbocharger blades on the rubber elbow,
Then, unhook the
cover retaining clips
and push the rear
of
the cover toward the
engine.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission fluid level is when the
engine
oil is changed. Refer to the Maintenance Schedule to determine
when to change your fluid.
See “Scheduled Maintenance Services” in the
Index.
How to Check
Because this operation can be a little difficult, you may choose to have this
done at a
GM dealership Service Department.
If you do it yourself, be sure to follow all the instructions here, or you could
get
a false reading on the dipstick.
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