[1retired06]

I am hestitant to say this since I have no personal experience with the 6.4, but if you can hold off and look for a low milage 6.7, as I read the diesel forums, the 6.7 is superior to, and ford has engineered into the 6.7 engine, solutions to the issues assocated with the 6.4 primarily regeneration. I have talked to a couple of folks who have owned both and theyn stress the 6.7 is an improvement over the 6.4 to include regeneration, power, and MPG.