Does your 6.7L Cummins have a blown head gasket?Join the club. At a minimum, make sure your have your head surfaced to ensure it is flat. We also HIGH..
Dodge 6.7L Cummins CCV Crank Case Vent Filter
All ‘07.5 and newer 6.7 liter engines have a crankcase vent filter that is located on top of the valve ..