>but won't ALL oil (including >Mobil One) break down eventually? What's eventually? Mobil 1 used to be advertised as 25K oil change (for consumers) Mobil 1 (Delvac 1, industrial oil) used to be (don't know if still is) promoted as NO oil change, just replace filter, add oil (when down) and send for oil analysis periodically, Avi Meron