Issues with my 2001 F-250 7.3L transmission continue...

2WD...My neighbor just told me he'd replace with a 2004 electronic transmission rather than another 2001. Says they're better. Not sure that's possible tho. Guy on the diesel forum says no. I have cross-posted this on the dieselstop forum. One guy says it sounds like a mechanical diode so important to flush the lines/cooler for metal fragments. They are zeroing in on the torque converter which they say sounds like a paint can being shaken -- makes quite a racket just before the transmission goes completely.