Quote Originally Posted by 12vdc View Post
For gasoline, crankcase ventilation is controlled by the PCV valve. You just need to maintain that PCV valve to avoid buildup of gunk and unecessary pressure.

For diesels, crankcase is open directly vented in the air-intake manifold that is why negative pressure amplifies the oil-mist being ingested back to the intake, hence the need to install OCC.
Sir, what occ brand will you recommend for my Toyota Fortuner 2016 Diesel?