Chevrolet 1994 Astro Passenger Owner's Manual page 232

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).
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).
0
Most trips are through dusty places.
If any one of these is true for your vehicle, then you need to change your oil
andfilter every 3,000 miles (5 000
km)
or 3 months - whichever comes
first
.
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.
Engine Coolanf 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 (-18°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.)
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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