The head studs allowed coolant to lock my engine and blow it to pieces. A $80,000 vehicle should not have cheap studs that don't work. I believed that Ford didn't care about quality anymore and these 6.4 diesels are the proof. I know that I am just one person and don't mean anything to a big company like Ford, but I want to remind Ford that it is people like me who make them a big company!!!! I tell all my friends to not buy a Ford diesel. I have spent at least $17,000 to fix my truck. I think I am owed at least a explanation why they sell such a sorry truck. my next truck will not be a Ford!!!!