There's no cleaning procedure in the service manual, but here's the removal procedure:
1. Remove the oil fill cap.
2. Remove the breather cover bolts.
3. Remove the breather cover (this is the big black cover that says "Dodge" and "Cummins" on it.
4. Disconnect the breather tube and lube oil drain tube from the breather.
5. Remove the breather tube mounting bolts.
6. Remove the breather from the cylinder head cover.
There's an o-ring where the breather enters the valve cover. Service manual says to use a new o-ring when you reinstall the breather, but I'd bet you could get away with using the old o-ring when you put it back together.
I'm not sure how to get the breather itself apart to clean inside it, but it might be apparent when you've removed it from the engine.
If you do this, take some pics of the inside of the breather if you can...
-Ryan
