Here goes. I have a 08 150 5.4 4x4
4r75e trans. So a little while back i started having ehat felt like slipping in first gear. I then blew a code for the oss sensor. I replaced both input and output. That did not fix the issue. Finally truck was driving great. Then went to turn around and no reverse. Truck moves forward in all gears. Even nuetral. It also seems to be stuck in 4 wheel low. Seeing how i cant drive over 30.
I replaced the tranny with a used one. And having the same exact issue. When i swapped the trannies i did the fluid and filter on the new used one. Also the fluid was still good on the old one. Any ideas. Would be greatly apreciated.

Thanks for the reply but already tried that. I apreciate the idea though