Buick RIVIERA 1993 Manual page 229

When to Change Engine Oil: See if any one of these is
true for you:
Most trips are less than 4 miles (6 km).
a It's below freezing outside and most trips are less
than 10 miles (16
km).
0
The engine is at low speed most of the time (as in
door-to-door delivery, or in stop-and-go traffic).
Most trips are through dusty places.
If any one of these is true for your vehicle, then you
need to change your oil and filter 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 Block Heater: An engine block heater can be a
big help if you have to park outside in very cold
weather, -20
O F
(-29 C ) or colder. If your vehicle has
this option, see ?Engine Block Heater" in the Index.
What to Do with Used Oil:
1
Used oil can be a real threat to the environment. If yo
change your own oil, be
sure
to drain all free-flowing oi
from the filter before disposal. Don't ever dispose of oil
by pouring it on the ground, into sewers, or into streams
or bodies of water. Instead, recycle
it
by taking it to
2
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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