Unfortunately it is. All the EPA crap does this to our trucks. Hurts the motor and gives lousy mileage. DPF and CAT delete and tuner are the only way to fix it. A mild tune will not hurt the truck and deleting will only make it last longer.
When these trucks go into regen diesel fuel is pumped into the cylinders on the exhaust stroke. with the rings relaxed some of it goes into the oil pan. Also it is using a lot of fuel to get the egts high enough to clean out the dpf. with the dpf and cat on mileage sucks
Had the same probs with my 2010. Tried the lemon law but no help there cause Ford could not duplicate the problem. Did a DPF/DOC delete and an 80 HP tune and all problems gone. The EPA junk is the usual culprit.