SO I was driving around town yesterday when all of the sudden, my truck dropped into neutral. So I pulled over, turned it off, turned it back on, but it kept doing it, right at 30 mph. I would be accelerating like normal, hit 30, then it would rev up like it would in neutral. I read that sometimes it is a OD issue, so i tried turning OD off and the truck runs [almost] like normal.

I've only found one thread that was decently helpful, and the guy basically had to get a tranny rebuild.

Has anyone else had this issue? Any advice?

(EDIT: I should mention I have a 5.4l)

 

I'm not an expert, but but maybe check the transmission fluid for burnt smell and fluid level.

 

Awesome... My 08 FX2 w/ a 4.6L is doing the same thing. I'll check fluids in a few hours. I have 132k on the clock.

 

So this is a common problem with these trucks, you have lost Over Drive. If you switch the OD off your truck will drive fine. There is a snap ring in the over drive piston inside the transmission that is broken and a piece of it goes through the Valve body and lodges into one of the valves causing it to stick. I know this because I just fixed mine and that's exactly what happened to me. There are plenty of videos and write ups about this.

Search F 150 lost Over Drive and a ton of info should be at your finger tips.

Part Number for the snap ring is F2VY7384B
Found at ford dealership only.
Also you'll need a new transmission filter, My dealership wanted 44 dollars, Autozone was 11.99
10-13 q of Mercon V fluid