Just got done doing my trans build and took it for a drive, drove nice and shifted smooth for about 5 miles then cel and stuck in 4th, P0762. I pulled the valve body and the valve was stuck, I touched the valve and it popped free. I pulled the valve out and didnt find any debris and everything looked fine so I put all back together and put in reverse to back off lift and the same thing instantly. Any ideas on what I should do to correct this?