Do I need an overhaul?

[Brock]

What you need to know is if the blow by is actual blowby or something else? Take your oil cap off, do you see blowby chuffing out there? You could have a shop do a proper blowby test.

I thought my motor was needing a rebuild but it turned out my new reman cummins turbo was boosting into my crankcase.

My local cummins just told me the 871 had a bad run of reman turbos where they would have to check every one before install because so many were bad.