1994 CHEVROLET SUBURBAN engine

Checking Things Under the Hood
Hood Release
To open the hood, first
pull the handle inside
the vehicle.
Then go to the front of
the vehicle and pull up
on the secondary hood
release, located just to
the passenger side
of
the center of the grill.
Lift the hood.
Your vehicle,
if it has
air conditioning, may
have a auxiliary
engine fan in addition
to the belt driven fan.
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Before closing the hood, be sure all filler caps are on properly. Pull down
the hood and close it firmly.
Cleaning Your Diesel Engine
NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm
or hot, or when it is running, you could cause
serious damage to it.
If you ever clean the engine, clean it only
when it is cold.
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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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NOTICE:
Don’t add too much oil. If your engine has so much oil that the
oil level gets above the upper mark that shows the proper
operating range, your engine could be damaged.
P
The engine oil filler
cap is located on the
driver’s side engine
valve cover.
Just fill it enough to put the level somewhere in the proper operating range.
Push the dipstick all the way back in when you’re through.
What Kind of Oil to Use
Beginning midyear 1993, oils of the proper quality for your vehicle will be
identified
with this new “starburst” symbol. The “starburst” symbol
indicates that the
oil has been certified by the American Petroleum Institute
(API), and is preferred for use in your gasoline engine.
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You should look for this on the front of the oil container, and use only oils
that display this new symbol.
You should also use the proper viscosity oil for your vehicle, as shown in
the following chart:
LIGHT DUTY EMISSIONS -GAS ENGINES
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAL VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
F
+ 100 '
+80.
+60
+4a.
+20 -
0-
C

- +38
. +27
-+16
.+4
'-7
- 18
I
SAE SW-30
PREFERRED
LOOK FOR
ONE OF THESE
LABELS
SAE 1OW-30
IF NEITHER SAE 5W-30 NOR SAE 1OW-30
GRADE
OILS ARE AVAILABLE, SAE 30
GRADE MAY BE USED AT TEMPERATURES
ABOVE
40 DEGREES F (4 DEGREES C).
DO NOT USE SAE 1OW-40, SAE 2OW-50 OR
ANY OTHER GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE 5W-30 is best for your vehicle. However, you
can use SAE 1OW-30 if it's going to be 0°F (- 1 8 O C) or above. These
numbers on
an oil container show its viscosity, or thickness. Do not use
other viscosity oils, such as SAE 1OW-40 or SAE 20W-50.
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HEAVY DUTY EMISSIONS -GAS ENGINES
RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
SAE
VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
"F "C
+loo - - +38
+80 --+27
+60 - - +16
t40--+4
+20 ---I
0 - --18
LOOK FOR
ONE OF THESE
LABELS
I
I
SAE 1OW-30
PREFERRED
SAE
5W-30
COLD
WEATHER
IF NEITHER SAE 5W-30 NOR SAE 1OW-30
GRADE OILS ARE AVAILABLE, SAE 30
GRADE MAY BE USED AT TEMPERATURES
ABOVE
40 DEGREES F (4 DEGREES C).
ANY OTHER GRADE OIL NOT RECOMMENDED
DO
NOT USE SA€
1OW-40, SAE 2OW-50 OR
As shown in the chart, SAE IOW-30 is best for your vehicle. However, you
can use SAE 5W-30 if it's going to be colder than 60°F ( 16°C) before your
next oil change. When it's
very cold, you should use SAE 5W-30. These
numbers on
an oil container show its viscosity, or thickness. Do not use
other viscosity oils, such as SAE lOW-40 or SAE 20W-50,
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If you cannot find oils with the new “starburst” symbol on the front of the
container, you should look for and use oils containing the following three
things:
SHorSG
“SH’ or “SG’ must be on the oil container, either by itself or combined
with other quality designations, such as
“SWCD,” “SH,SG, CD,”
“SGKD,” etc. These letters show American Petroleum Institute (API)
levels
of quality.
less)
OR
SAE 1OW-30 -Vehicles with Heavy Duty Emissions (8501 GVWR or
more).
e SAE 5W-30 -Vehicles with Light Duty Emissions (8500 GVWR or
Energy Conserving I1
Oils with these words on the container will help you save fuel.
These three things are usually included
in a doughnut shaped logo (symbol)
on most containers.
If you cannot find oils with the “starburst” symbol, you
should look for
oils with the doughnut shaped symbol, containing the three
things noted above.
NOTICE:
If you use oils that do not have either the “starburst” sym\
bol or
an
API SH or SG designation, you can cause engine damage not
covered by your warranty.
GM Goodwrench@ oil (in Canada, GM Engine Oil) meets all the
requirements for your vehicle.
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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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