I have an 03 dually with the 5.9 Cummins and 6 spd manual. There is some blowby, not bad but enough to notice it when the truck is idling and you look under the front. I found some seals and an open ended ring in the dash pocket when I bought he truck, I wonder if the turbocharger seals were changed and not put back right, and if that is causing my blowby. (See the bottom cause in the chart)   Anybody have any thoughts on this ?