I have a 2008 F150 4wd with the 4.6. Recently reverse stopped working and I got a code of P0720. I replaced the output speed sensor and reverse began to work for about a week or so. Then i began getting the code P0715, so I replaced the input speed sensor. The truck now will move in reverse every so often, but not always. Also now the O/D off light flashes and I get a trans fault. I'm hoping it's not a bad transmission. Just wondering if anyone has had an issue similar to this and gotten it fixed. Truck barely has over 100k on it.

 

Remove pan, replace wiring harness, recheck.

Also remove bulkhead connector from tranny, inspect, clean all pins and contacts with QD electronic cleaner, and re assemble. See what happens b4 spending a fortune on another tranny. This fixes all of my crown vic tranny issues have had over the years.

 

Reverse doesn't use anything electrical. It isn't an electrical connection or sensor. It's something mechanically wrong inside the transmission. My guess is a failing seal in the reverse clutch.

 

yeah. and its going to have to come out. is reverse the only one giving problems? usually forward one or 2 forward ranges doesnt work right either