I am an avid supporter of Royal Purple. I found a study many years ago that put me into this thinking. I have tried to relocate it with no luck, but I did find these studies. I would like your opinion from personal experiences. If better studies are out there I am interested in seeing them.
But, unfortunatly this one is for car grade oils. Still it is interesting.
This study is interesting but hard for me to follow. I'm not a gearhead. For me one picture is worth a thousand words. No pictures in this study: Diesel Oil