so my truck decided to stop goin into drive today and when i revd it to 1500 rpm it would slam into gear and the o/d light would flash and it would go into trans fault and get a p0720 code i brought it to a mechanic and they dropped the transmission pan and it needed a rebuild i got the tranny rebuilt and still doing the same thing just now it goes into drive and gets to fourth gear and than goes into trans fault and the code appears so i changed the speed and turbin sensors like the code said and still it goes into trans fault and the codes appear so we brought it directly to the dealership were they checked the electrical and said it was all good no shorts or wireing issues and they replaced the sensors with true ford sensors not auto zone ones and said it has to be the pcm so i got a new pcm and had it re flashed and still the same thing trans fault and p0720 when it gets to fourth gear the mechanics said they have never seen this before and are starting to think that maybe its internal when i just had the tranny rebuilt i now have new tranny new pcm and all new speed and turbin sensors and theres no electrical issues! what the heck is wrong!????

 

You replaced the turbine speed and the vehicle speed sensors. Why? The code is for the OUTPUT speed sensor, a totally different sensor that what you're talking about.

There are four ways that this code can set.
1. A bad output speed sensor.
2. A wiring issue (open or short) in the two wires to the output speed sensor.
3. A damaged drum inside the transmission for the output speed sensor to read.
4. A bad PCM.