I was wondering about that myself on the new ones. How often are you guys filling that up?

True. No doubt about it. The new 6.7's are indeed incredible pieces of technology running 400hp and 800 ft-lbs of torque, but along with all that come other complications and a whole new plethora of associated failure points. The engines themselves are strong, but I'm hearing a lot about NOX sensor failures, DEF faults, HPFP failures from hyper-sensitivity to wet fuel, etc. If one were to simply asked which Ford diesel was/is the best...simply put, I think that most folks would agree that the most dependable, most reliable, most bulletproof engine was indeed the old 7.3s. The comfortable average lifespan was easily 300K+ miles without any worry.

Not really a pain at all. Just a minor annoyance. It's relatively cheap and you can fine it at most every gas station car parts place anymore. The average I'm hearing is that the 2.5 gallons will last approximately 5,000 miles, depending on usage and driving habits. Ironically, the harder you work the trucks, the longer it lasts. You can't let it get low though, because the computer will begin squawking at you with warnings, until eventually it goes into limp mode until finally the truck will simply shut down. Thanks to the government's infinite wisdom.

3/4 of the time I let the dealer install everytime while getting an oil change..its the same cost as I can get at the truck stops..they just pour it in.. On the Fords its right next to the gas cap..on my GMC its under the hood..a little more of a pita. The 12 Cummins HO it is not required, but that will change for 13... Just turned 109k today on the 11 F250...running strong.