pete7996

04 f150 xlt 4.6 140k, so im driving along today and my tranny just starts slipping. come to a light 1st gear fine,2nd gear fine,wont shift to 3rd, turn off the od button and it shifts fine. then 40 mph with od off, if i turn od back on its like its in neutral. turn it back off and it grabs 3rd. OD on slips like its in neutral,OD off drives like normal. no check engine light, no codes in the pcm. no codes for trans,abs,and the speed sensor is reading on my scanner.fluid is full and not burnt.Looked at all the wiring and plugs, they all look ok. I work at a local repair shop but we dont get into transmission rebuilds at all. my tranny guy(who we send our trans work to) says its common and needs an overhaul, I trust his judgement but it just seems strange. Thoughts?