I have a 2008 6.4L and I'm the 3rd owner. the truck has 157k on it and I've noticed since I bought the truck there has been a bit of blue smoke coming from the exhaust when I sit at a stoplight and when I get on the throttle. I have the H&S mini maxx installed and I have the dpf removed and deleted the egr is still present on the truck. Also I changed the oil in the truck with rotella and I've drove it approx. 1000 miles and I checked the oil today and its on the minimum mark. What could be some things to check to try to pinpoint the issue. Help please.