Thanks! Everything I've researched seems to say that the 6.7 fuel system is far more reliable than the 6.4. We did add an extended warranty based on some recommendations from friends that have or have had these trucks. We made sure that it was a quality warranty that covers everything except cosmetic and regular wear items brake pads, filters, oil changes, tires, and then glass. But we have glass coverage through our insurance so didn't want that. It's a $0 deductible at the dealer's network or up to $100 deductible at any Ford dealer nationwide. I'm going to make sure that anytime something seems wrong or has an issue over the next 4 years that I get it in there and get it checked out