700R4 no overdrive even after tcc 4th gear lockup installed

I was driving on the highway and I went to pass another car it down shifted. Then after that I lost overdrive. It would into overdrive when cold but would kick rite back out. I then installed a dual contact pressure switch or what is called a tcc 4thgear gear lockup switch but now it doesn't go into 4th gear or overdrive. I did find metal fragments in the trans pan.