904 brakes torgue converters

Hello. I have Mopar 360+904(lock-up)+8 3/4

Problem is my trans brakes my torgue convertors. This is my second that went crap. Snout in the TC that drivers oil pump cracks. 1 half of it cracks. It only last about 400 miles, then fails. I have rebuildet trans by expert and it has new oilpump etc. I also hac TCI (SFI sertifikated) flexplate, its thik metal and stroger than stock flexplate, i think, it is balaced to 360 engine and i use zero balanced TC. "snouts" that what is between engine and trans for agliment, they are there.

I have no idea what cause this problem, one thin what comes to my mind is that the flexplate is bent and brakes TC? I need help and aim very pissed off by this situation. :banghead::banghead::banghead:

Thanks! ps. sorry bad english.