GMC SIERRA 1994 Manual page 269

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 i n your gasoline engine.
YOU should look for this on the front of
the
oil container, and use only oils
that display this new symbol.
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