I'm really confused about this: I've used the Amsoil 5W-30 Synthetic since day 1 on my 2001 Honda Prelude and I'm very happy with it. People have been recommending the Series 2000 0W-30, but looking at the specs on Amsoil's site, the 5W-30 seems superior (higher kinematic [email protected]*C, lower Noack volatility, better 4-ball wear test, and the same TBN). Here is my dilemma: - Four-ball wear test The spec for the Series 2000 0W-30 is 0.373mm at 150*C, 1800RPM, whereas the 5W-30 is 0.35mm at 75*C, 1200RPM. What gives, why do they have different testing procedures? Which is better? - Noack volatility The Noack volatility for the 0W-30 is [email protected]*C, and for the 5W-30 it is [email protected] an unspecified temperature. Do I assume it is also @250*C? - Cold crank simulator The 0W-30 is [email protected]*C, whereas the [email protected]*C. Why don't they specify the viscosity at the same temperature so one can make an informed decision. -High Temperature/High Shear Viscosity cP The 0W-30 is specified as [email protected] unknown temperature, whereas the 5W-30 is [email protected]*C. Should I assume the 0W-30 was measured at 150*C as well? Maybe someone could shed some light on this?