Metal in the pan, shifts good, fluid great any guesses before I pull it down?

So here's what happened. Pulled the trans and not a thing wrong inside, not even a spec of metal. Took a hard look at the converter and after spending a few hours draining it over time, not one single piece of metal came out, took it to a shop and had it flushed for 30 min and not a spec of material came out. Pulled the trans cooler and full of ****. So the cooler a friend gave me that he picked up somewhere was full of trash and it went in the pan after running, that dacron filter did its job cause that where it stayed. Need to flush the lines and get a new cooler and put it all back together. Dumb *** luck good or bad not sure yet. Strangle my buddy hell yes.