So I was driving my 2004 6.0 auto on the freeway today when the tow haul light randomly started flashing, nothing felt wrong until I stopped, then when I went to pull away it wouldn't shift down from 5th according to my livewire ts says under the commanded gear gauge. It shifts into 6 and overdrive fine. I turned the truck off, the light went off but as soon as I put it in drive it jumped around from 1-2-5 and back down until it locked in 5 again and the light started flashing again. Anyone know what this could be? I'm about to trade the truck in and really need this fixed!!!!

 

We're going to need the actual codes when the tow/haul light flashes it means there is a code. Maybe a moderator will see this and move you to the 6.0 section the guy that was part of the team that designed your transmission hangs out over there. If you want to know anything about that trans Mark K. is the man he's forgotten more about transmissions than most of us will ever know.