I've seen other engine types that the oil drain passages had become partially and or fully blocked. The oil would all get pumped to the top of the engine, but took too long to drain back. In severe cases, the oil pump would be starved and you'd notice a drop in oil pressure at high rpm.

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Remember, Safety Third!
'99 E300 Turbodiesel, '82 300TD, 1996 12V Cummins Turbo, '94 Neoplan - Detroit 6V92TA