If the 6.0 was not a bad design Ford would not have been in a class action suit & would not have sued IH over the faulty design of the oil & egr cooler. The company "Bullit Proof Diesel" would not be in business but they have designed aftermarket parts to fix the shortcomings of that eng. I myself bought 4 of them for work trucks and parked them for sale before the warranty ran out. We knew we could not afford them without warranty. Your success story is the exception to the rule. You are a lucky man. When Bullit Proofed it is a great eng with a good trans behind it. The biggest killer of these is improper coolant maint. Silicates in the coolant pluggs the coolers. It is good the hear a positive story but check the cond & balance of your coolant often. Good luck.