engine CHEVROLET SUBURBAN 1994 Owners Manual

DIESEL ENGINES
I RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
SELECT THE SAE GRADE 011 BASED ON
THE EXPECTED TEMPERATURE RANGE
I BEFORE NEXT OIL CHANGE
HOT
WEATHER
+loo -
+60 - - +16
+32 -- 0
0 - - -18
-20 - - -29
________
COLD
WEATHER
LABEL
SAE 1OW-30
SAE 15W-40
PREFERRED
above 0°F (-18%)
- SAE r 30
DO NOT USE SAE 1DW-40, SAE 2OW-50 OR
ANY OTHER GRADE OIL NOT RECOMMENDED
SAE 15W-40
As shown in the viscosity chart, SAE 15 W-40 is best for your vehicle.
However, you can use
SAE low-30 if it’s going to be colder than
32°F (0°C) before your next oil change. When it’s very cold, below
0°F (-1 8”C), you should use SAE IOW-30 to improve cold starting.
Also, SAE 30 may be used at temperatures above freezing, 32°F (0°C).
These numbers on the oil container show its viscosity, or thickness. Do
not use other viscosity oils such as SAE 10W-40 or SAE 20W-50.
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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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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.
Wait at least 30 minutes before checking the transmission fluid level if you
have been driving:
0 When outside temperatures are above 90°F (32°C).
0 At high speed for quite a while.
In heavy traffic - especially in hot weather.
0 While pulling a trailer.
To get the right reading, the fluid should be at normal operating
temperature,
which is 180°F to 200°F (82°C to 93°C).
To check transmissionfluid hot: Get the vehicle warmed up by driving
about 15 miles
(24 km) when outside temperatures are above 50°F (IOOC).
If it’s colder than 50°F (IOOC), drive the vehicle in “D” (3rd Gear) until the
engine temperature gage moves and then remains steady for
ten minutes.
Then follow
the hot check procedures.
To check transmissionfluid cold: A cold check is made after the vehicle has
been sitting for eight hours or more with the engine off and
is used only as a
reference. Let the engine run at idle for five minutes if outside temperatures
are
50°F (10°C) or more. If it’s colder than 50°F (IOOC), you may have to
idle the engine longer. Should
the fluid level be low during a cold check,
you
must perform a hot check before adding fluid. This will give you a more
accurate reading of the fluid level.
To check the fluid hot or cold
Park your vehicle on a level place.
e With the parking brake applied, place the shift lever in “P’ (Park).
With your foot on the brake pedal, move the shift lever through each
gear range, pausing for about three seconds in each range. Then,
position the shift lever in
“P” (Park).
Let the engine run at idle for three minutes or more.
Then, without shutting off the engine, follow these steps:
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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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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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What to Use
use a mixture of one-half clean 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” with a complete coolant flush and refill. If you use
this mixture, you don’t need
to add anything else.
NOTICE:
If you use an improper coolant mix, your engine could overheat
and be badly damaged. The repair cost wouldn’t be covered by
your warranty.
TOO much water in the mix can freeze and crack
the engine, radiator, heater core and other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when the engine is cold
and follow the steps under “Adding Coolant” for
the proper way to add
coolant.
If you have to add coolant more than four times a year, have your dealer
check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to add extra
inhibitors
or additives which claim to improve the system. These
can be harmful.
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Adding Coolant -Gas Engines
The coolant recovery
tank is located on the
passenger side at the
rear comer of the
engine compartment
To Check Coolant
When your engine is cold, the coolant level should be at COLD, or a little
higher. When your engine
is warm, the level should be up to HOT, or a little
higher.
To Add Coolant
If you need more coolant, add the proper mix at the coolant recovery tank.
Add coolant mix at the recovery tank, but be careful not to spill it.
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Adding Coolant -Diesel Engines
.. The coolant surge tank
is located on the
passenger side at the
rear corner
of the
engine compartment
To Check Coolant
When your engine is cold, the coolant level should be at the COLD mark,
or
a little higher. When your engine is warm, the level should be above the
COLD mark.
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 tank, but only
when the
engine is cool.
Open the bleed valve
on the thermostat housing to allow trapped air out of
the system. Close the bleed valve when coolant begins to flow out.
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