I just bought at 96 mustang gt. It has an auto trans and it shifts well through most of the gears except when I floor it on the freeway and it attempts to shif it neutrals and just revs free until I let off throttle. I’ve done some research and most people say it’s something to do with the overdrive servo. I also noticed once on hard acceleration it neutrals going 2nd to 3rd. Is this gonna be a remove the trans and have to rebuild it or just a valve body issue?