[TR] Synthetic vs. Regular Oil

[Randall]

> The FAA and aircraft engine manufacturers did approve Mobil 
> AV 1 (an aviation spec synthetic oil, not Mobil 1 car oil) 
> for use in aircraft engines. This approval was later 
> rescinded, but I disremember the reason why.

Ok, having a particular aviation oil blend rescinded makes a lot more sense.
(Not that I doubted you at all, John.)  But that's a far cry from
disallowing all synthetic oils; and still has virtually nothing to do with
which oils work well in car engines running unleaded fuel. (Even "low lead"
Av gas contains far more lead than automotive fuel ever did; plus as I
understand it lacks the halogen "lead scrubber" compounds commonly used in
automotive fuel.)

Randall