Went to dealer on trans issues have an 11 EB with 3.73 rear end, max tow. I felt a shuttering at times and a stop bump when stopping. They couldnt duplicate shuddering but did duplicatet the stop bump. For the stop bump according to Ford that normal saw the email the tech got. For the shuttery they installed friction modifiers or something of that nature anyways and thats supposed to be the solution. For now thats all i got.

 

dealer verified as well that the trucks run rich for a while and they have noticed better fuel mileage after time goes by. Mechanic couldnt tell me the miles it ran rich but said it did.

 

It's probably the slip yoke sticking. I had the same issue in my truck. I took it to the dealer with the TSB for sticking slip yoke and they fixed it in half a day.