Putting Tranny Fluid In The Crankcase???

I remember reading about putting some Tranny fluid into the crankcase along with some oil???? i tried searching but really didnt know what to type in to bring this back up. whats the skinny on this??

Tranny fluid is supposed to swell the seals, to help slow leaks. Ive never tried it, so I wouldnt know for a fact. Just read on the good old Intarweb.

Not really a good idea to do so, IMO.

I've done it.

It's an old mechanic's trick; the detergents in the tranny fluid are supposed to help clean up gunk in the engine. I put maybe a third of a litre in and run it for 10 minutes or so. (Maybe take it for a little drive.) I've done it in plenty of my vehicles, and haven't really noticed good or bad from it.

Seafoam, Marvel mystery oil, or transmission fluid.... its up to you what you want to use to try to clean up inside of the engine.

I did that once for about 100 miles.

Turned my light little tick into a deadly bearing knock in exactly that time.