[doru]

So what is the difference between an oil change and the OFHG gasket R&R?
because in both cases the oil filter is out and the passages are open. No issues after oil changes but problems after OFHG R&R.
The oil priming theory does not hold water. I also used 0 grade oil for the last 20 years or so, never primed the system after oil changes or after OFHG R&R (which were quite a few). On older engines, like M54 as an example, the mating surface is perpendicular, so chances for debris to fall in is minimal. On the N5x is slightly canted. If debris is caked on top and between the mating surfaces of engine and oil filter housing (hard to see because it's in the back - actually side, but not visible), if not cleaned, it can fall inside.

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