The Frantz-style bypass filter element I sold for the LuberFiner 750 big rig filter canisters had a 1 micron filtering capability back in the late 1970's. We changed the filter every 10,000 miles, topped off the crankcase with 1 gallon of fresh oil, and never changed the oil in the sump. With oil capacities of 10-12 gallons that was a huge saving in preventive maintenance cost for the rigs I serviced. Some of those rigs had 100,000+ miles on the oil with no loss of efficiency, confirmed by the spectrometric analysis we did at every filter change. Oil doesn't wear out- - - -it just gets dirty.
Jerry

Last edited by Hotrod Lincoln; 03/18/2014 5:47 PM.
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