Originally Posted By: Captain_Klink
i've been using 50:50 synthetic 5w30 : conventional 5w20 in my Subaru for a couple of years already. after reading Dr. Haus's article on oil here, it makes sense: the problem with oil, is that it is too thick.
Dr. Ali E. Haas is a cosmetic plastic surgeon, not a mechanical engineer nor a tribologist. He probably knows more about skin oil than engine oil. The necessary viscosity of oil is more related to the bearing clearances than the flow rate. In the writings of his that I've read, I've seen nothing about the hydrodynamic wedge of oil in a journal bearing. This is what keeps the parts separate, not the oil flow. Flow is necessary to make up for leakage, carry away heat and debris, but not to keep the parts from touching.