Chevrolet 1993 Astro Passenger Owner's Manual page 248

Service & Appearance Cam
KO704
What Kind of Oil to Use:
Look for three things:
SG
SG
must be on the oil container, either by itself or combined with other
quality designations, such as SG/CC, SG/CD, SF, SG, CC, etc. These
letters show American Petroleum Institute (API) levels of quality.
NOTICE
I
you use oils that don't have the
SG dl
3maae not covered bv vour warrantv.
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