If manufacturers were really interested in doing a good job of filtering oil, they would use the system that Cummins, Detroit, Catepillar, and just about every other heavy duty Diesel manufacturer has used for over 50 years- - - -two filters. The full flow filter is for straining out rocks, marbles, bowling balls, and other big stuff that can compromise the lubricating film between the crankshaft and the bearings, stuff that's bigger than the clearance specification. Then there needs to be a bypass filter with media fine enough to strain out the tiny particles that get through the primary filter. There is no way to flow enough volume through a good bypass filter to meet the engine's lubrication requirements. The filter I sold and installed on heavy duty Diesels for years was the Frantz system, the one that used tissue paper as a filter medium. It strained out particles down to 2 microns, approximately 50 times as efficient as a full flow filter. It also took several minutes for one gallon of oil to flow through a canister the size of a LuberFiner 750- - - -6" in diameter and 16" tall. Obviously, a free-flowing primary filter was needed to catch the big chunks and protect the bearings, but a full flow filter is a whiz-poor method of actually doing any efficient filtering of the oil.
http://www.frantzfilters.com/wp-content/uploads/2015/07/96-percent.jpgJerry
