The info posted by madmaxx came from the site BITOG (Bob Is the
Oil Guy) but "Bob" had nothing to do with it. It was provided by a medical doctor named A.E. Haas who is not a tribologist and whose extensive views are not embraced by a large number of BITOG members. Dr. Haas does, however, put his money where his mouth is by running very low viscosity oils in very expensive cars. For example, he uses 0W-20 in his Ferrari Enzo. I believe the factory calls for 10W-60.