I have never used MMO in the oil however....... It often gets added to the
fuel.

On Mon, Mar 11, 2013 at 1:11 PM, Loren Busch <starwagen@gmail.com> wrote:

>  RE: Marvel Mystery Oil
> Although there are some on this list that use MMO in various ways there is
> little or no need for such with today's detergent oils.  If you had an
> engine that had been run way to many miles without an oil change then
> maybe.
> I have personally seen internal parts from a WBX (valve lifters) badly
> scored or actually worn through from an engine that had run MMO all the
> time for many thousands of miles.  Was MMO to blame? Maybe, maybe not.  But
> since it thins out the oil in the engine MMO was a suspect in that case.
>