Rebuild time

[Waterloo]

Get the programming sorted out ASAP. And like schISM stated, if it is not using oil and or there is an issue with the head, I would not in frame, I would work the truck. I worked in the oil field too, like others here, fuel economy is going to be what it is. If fuel economy is your only reason to in frame, save your money. Fix the programming, that will do more for your fuel mileage than an in frame. Put your hard earned money to better uses.