service CHEVROLET SUBURBAN 1994 Owner's Guide

Water in Fuel
Sometimes, water can be pumped into your fuel tank along with your diesel
fuel. This can happen if a service station doesn’t regularly inspect and clean
its fuel tanks, or if it gets contaminated fuel from its suppliers.
If this happens, a “WATER IN FUEL” light will come on. If it does, the
excess water
must be drained. Your dealer can do this for you.
This light
also should come on briefly when you start your engine, as a
check. If it doesn’t, have it fixed so it will be there to let you know if you
ever do get water
in your fuel.
If the light comes on at any other time, use this chart.
“WATER IN FUEL” LIGHT CHART
Problem
Light comes on intermittently.
Light stays on:
1. At temperatures above
freezing.
2. At temperatures below
freezing.
Recommended Action
Drain water from fuel filter.
Drain fuel filter immediately.
If no
water can be drained and light stays
on, see your dealer for assistance.
Drain fuel filter immediately. If no
water can be drained
- water may
be frozen. Open
the air bleed valve
to check for
fuel pressure. If no fuel
pressure
is present, replace the fuel
fi 1 ter.
3. Immediately after refueling - Fuel tank purging required. See
large amount
of water possibly your dealer for assistance.
pumped into fuel tank.
Hesitation or “flat” performance at
high speed or during hard acceleration
may be an indication of premature fuel filter plugging due to dirty or
contaminated
fuel. The filter element may need to be changed if this
happens. See your dealer for assistance.
If you drive when this warning light is on, you can damage your
fuel injection system and your engine.
If the light comes on right
after you refuel,
it means water was pumped into your fuel tank.
Turn
off your engine immediately. Then, have the water drained
at once.
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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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Air Cleaner
Refer to the
Maintenance Schedule to determine when to
replace the air filter.
See “Scheduled
Maintenance Services” in the Index.
NOTICE:
If the air cleaner is off, a backfire can cause a damaging engine
fire. And, dirt can easily get into your engine, which will d\
amage it. Always have the air cleaner in place when you’re drivin\
g.
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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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WOW to Add Fluid
Refer to the Maintenance Schedule to determine what kind of transmission
fluid to use. See “Recommended Fluids and Lubricants’’ in the Index.
If the fluid level
is low, add only enough of the proper fluid to bring the
level up to the
COLD area for a cold check or the HOT area for a hot check.
It doesn’t take much fluid, generally
less than a pint. Don’t overfill. We
recommend you use
only fluid labeled DEXRON@-I11 or DEXRON@-IIE,
because fluids with that label are made especially for your automatic
transmission. Damage caused
by fluid other than DEXRON@-I11 or
DEXRON@-IIE is not covered
by your new vehicle warranty.
After adding fluid, recheck the fluid level as described under “How to
Check.”
When the correct fluid level is obtained, push the dipstick back in all
the way; then flip the handle down to lock the dipstick
in place.
Manual Transmission Fluid
When to Check
A good time to have it checked is when the engine oil is changed. However,
the fluid
in your manual transmission doesn’t require changing.
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.
NOTICE:
Too much or too little fluid can damage your transmission. Too
much can mean that some of the fluid could come out and fall on
hot engine parts or exhaust system, starting a fire. Be sure to get
an accurate reading if
you check your transmission fluid.
Check the fluid level only when your engine is off, the vehicle is parked on
a level place and the transmission is cool enough for you to rest your fingers
on the transmission case.
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When to Check and What to Use
Refer to the
Maintenance Schedule
to determine how
often you should
check the fluid
level
in your clutch master
cylinder reservoir and
for the proper fluid.
See “Owner Checks and Services” and “Recommended Fluids and
Lubricants’’
in the Index.
How to check
The proper fluid should be added if the level does not reach the bottom of
the diaphragm when it’s
in place in the reservoir. See the instructions on the
reservoir cap.
Rear Axle
When to Checkand 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.
Add enough lubricant
to raise the level
to the
bottom
of the filler
plug hole.
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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
(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 -20°F (-29”C), or -34°F (-37°C) in
Give boiling protection up to 258°F (1 25°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Canada
and for vehicles with the cold climate option.
Let the warning lights and gages work as they should.
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Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its many parts have to
be of top quality and work well together if the vehicle is to have really good
braking. Vehicles we design and test have top-quality
GM brake parts in
them, as your vehicle does when it is new. When you replace parts of your
braking system
- for example, when your brake linings wear down and
you have to have new ones put
in - be sure you get new genuine GM
replacement parts. If you don’t, your brakes may no longer work properly.
For example, if someone puts
in brake linings that are wrong for your
vehicle, the balance between your front and rear brakes can change, for the
worse. The braking performance you’ve come to expect can change
in many
other ways
if someone puts in the wrong replacement brake parts.
Other Maintenance Items
Front Suspension and Steering Linkage
Your maintenance schedule will tell you how often to lubricate the fittings.
See “Recommended Fluids and Lubricants” in the Index for the proper
lubricant to use.
Front Wheel Bearing
Your vehicle has front wheel bearings that must be cleaned and repacked.
Your maintenance schedule will tell you how often this must be done.
Front Shock Absorbers
The front shock absorbers of your vehicle do many things. They help the
vehicle ride smoothly and also control the travel of the suspension system.
When the shock absorbers are serviced, any replacement shock absorbers
must be the same as the original equipment shock absorbers
in both
extended length
and strength.
I NOTICE:
If you use shock absorbers that are not the same as the original
shock absorbers, the shock absorbers or suspension system
could be damaged.
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some feature of your vehicle that you can get along without-like the radio
or cigarette lighter-and use its fuse, if it is of the value you need. Replace
it as soon as you can. See “Fuses and Circuit Breakers’’ in the Index
for
more information.
Exhaust System
To help prevent damage to your exhaust system, do not continue to drive
your vehicle if you notice:
Engine misfiring
Loss of performance
Other unusual operating conditions
Have your engine and exhaust system serviced regularly.
Three- Way Catalytic Converter (gas engines)
Your vehicle’s three-way catalytic converter is designed to reduce the
pollutants in your vehicle’s exhaust. Use only unleaded fuel in your vehicle.
If you use leaded fuel, you could damage your three-way catalytic converter
and other engine components.
Three- Way Catalytic Converter (diesel engines)
Your vehicle’s three-way catalytic converter is designed to reduce the
particulates in your vehicle’s exhaust. If your vehicle’s three-way catalytic
converter ever needs to be replaced, it must be replaced with a three-way
catalytic converter intended for use with diesel engines only.
Engine Contro/ Module System (All T61 equipped
vehicles and diesel engine vehicles below
8,500 lbs. GVWR)
Gasoline Engines
This system has an oxygen sensor (02) that helps keep your engine’s
air-fuel mixture at a proper level. Use only unleaded fuel in your vehicle. If
you use leaded fuel, you could damage your oxygen sensor
(02) and
three-way catalytic converter.
Diesel Vehicles Below S,5UU LBS. GVWR
This system monitors engine speed and throttle position. It adjusts exhaust
gas recirculation to limit emissions.
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