I'll throw in my 2 cents. First, ask the lab to confirm the high Fe number. I'll continue assuming that the iron is confirmed high.
The dirt ingestion is a minor problem that doesn't account for the elevated Fe number. I've seen numerous UOAs that had silicon at this level without a similar iron number.
My guess is that you have some severe fuel dilution problems. It shows up as 1%, but as much as the truck is driven, it is boiling off most of the fuel. I suspect that the excess gasoline is washing the oil off the cylinder walls, and causing elevated Fe numbers. The low flash point suggests that there is something in the oil in addition to the Mobil 1. The LC or VSOT shouldn't cause a flash point this low. So my guess is fuel.
Fuel could be coming from several sources. Perhaps the oil temperature is too low (stuck thermostat?). I don't think so because the water is 0%. Could be a bad oxygen sensor or water temp sensor. The computer might think the engine is cold, and is supplying too much fuel. Is fuel mileage normal?
My best guess is that you have some leaking fuel injectors. Run some Techron through the system, or get it professionally cleaned.
I would also suggest that you get Terry to interpret this. You have some severe problems that need to be addressed. This is when Terry's service is particularly valuable.
