Using an SM-Rated Oil When an SG-Rating is Recommended
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Question:
Using an SM-Rated Oil When an SG-Rating is Recommended
I just purchased a '92 Corvette and after changing the oil to Mobil 1 Extended Performance I noticed on the hood that it recommends an oil with the API rating of SG. After looking at the empty container it does not have this rating. Is this safe for my vehicle?
-- Larry Morgan, Auburndale, FL
Answer:
API ratings are backward compatible to previous generation ratings. This means that an API SM quality oil, which is the latest API rating, is recommended where API SL, SJ, SH, SG were originally required.
