[s-cars] not the usual oil question

[Mike Fitton]

The manual says API SF or SG rating.  I know what the S means, but I'm 
not completely clear on the F or G part.  I remember looking at Mobil 1 
last time I bought it, and it was neither SF nor SG.  Kind of 
disappointed with Mobil 1 lately for lots of reason, but I think this is 
the last nail in that coffin.  Lots of people have been running Mobil 1 
for like a decade or more by now, so I'm thinking it can't be that 
crucial.    So suppose I want to run an oil that carries an SM rating.  
It also carries a few VW ratings, incidentally.  Is that acceptable, or 
should I really try to find something SF/SG if I can?

-Cheers!
Mike