Hi,I have a 2004 explorer that had the rev. and forward not going in to gear unless you reved up the motor. so I tried the fixes that every one on line suggested...1st I puled the pan and checked the reverse piston,then I puled the solenoid block and tested the circuits and each solenoid,when I pulled the reverse piston I saw a very small piece of flat copper like a washer maybe,,,,so I went ahead and pulled the tranny looking for what was being shredded in there. well I've got it all apart and found a couple more small pieces in there,I think it was a copper or brass washer above or below one of the planetary gears since i can't find any other parts the same material....but there are no sings of ware on any parts,so any suggestions on what else to check?