I'm looking into purchasing a used Super Duty and I was wondering which engine to go with. I've heard some bad things about the 6.0 but thats usally coming from people who own the 7.3. I've only owned gas trucks up until now but I really want to purchase a diesel. Is it also true that Diesels engines' have a much longer lifespan than gas? The trucks in my price range tend to have about 80k on them and i've been told that 80k is just about getting broke in for a Diesel. Any light you can shed on this subject will be greatly appreciated.