I have a 97 f250 powerstroke remanufactured e4od. I started having a hard shift into 2nd and a delayed into 3rd. So I dropped the pan checked the filter and fluid still pretty and red no burnt smell no excessive metal shavings. So I replaced fluid and filter anyways cleaned connectors. Test drive did good no hard shift but a delay in every gear. I drove it for about 2 weeks 48miles round trip to work and home 5 days a week it started shifting better than it ever has smooth in and out of every gear no delayed shifts. That lasted about a month and it started acting like it was slipping through the gears it still pulls and shifts normal but under any kind of hard load rpm just climb like it's slipping but it's still pulling and shifting out. I had my transmission guy test drive it and he said felt like the valve body gasket was losing pressure and I needed a new valve body gasket. So yesterday I replaced the valve body gasket it went smoothly everything was again pretty fluid no debris no burnt smell. It takes gear alot better no delay into reverse or drive nice firm shift into gear it held first gear rpm stayed consistent with the load. It didn't act like it was slipping through the gear. So I took it down the road and after first gear same thing if stomp on it rpm shoot to 3 and hold and it runs through every gear like that. Just like if it was a cvt transmission. I'm completely lost.