ihagfo has the right idea on the first page of this thread. I have an 06 6.0 and felt it was worthwhile to take it to GA to have the guys at powerstrokehelp.com do a 6K dealerproof (someone got the rights to "bullet proof" so they can't use it). Around 100k to 120k is when the problems usually started showing up. IF you have no current problems with the engine, that's the way I would go. For the lower dollars up front you have the potential for a long lasting truck with other great features. PM for details, or Google powerstrokehelp and see what they offer. hth