🚀 go-pugleaf

The recent submissions on Syn vs Petro oils has raised a few questions:

The consensus seems to be that syn oils should not be used in an
engine that already has 40-50K miles on it (cause of their
superior detergent properties).  Well what if the engine were
first flushed out (one or more times) with something like Rislone?
Would that alleviate the deposits problem?  (I have no idea how
well Rislone or similar products work, but have been told that
running it in the engine for 5-15 minutes right before an
oil change helps flush out deposited crud.)


Alternatively, what would happen if a person were to gradually
wean the engine from Petro oils over to Syn oils.  Assuming
they do mix, could a person start out with, say, 1 qt of Syn
oil and the rest Petro oil, and gradually work up to 100% Syn
oils over the next few oil changes?  (Or do Syn and Petro
oils resist mixing, such that putting them together in the
crankcase is madness?)


One more ancillary question   Does anyone know anything
about the virtues of oil additives such as Bardahl #2? (or
is it #1?).  These are supposed to improve the lubricating
ability of conventional oil; (I believe they are wetting
agents that at least reduce the amount of oil that drains
off surfaces when the engine is stopped).  I'm NOT talking
about "oil life extenders," like STP, for oil that is long
due to be replaced...  we needn't waste electricity discussing
STP.


Any light that you can shed on this is appreciated.


  -Ron Pankiewicz