Second oil analysis for my SRT's 392. Previous interval was PU 0w40, this run was M1 0W40. Looks like its breaking in fine, I wouldn't really attribute any change just to the M1 vs the PU. In fact they look more similar here than VOAs posted elsewhere might hint. The M1 did hold viscosity and TBN better, I still think its a better oil than PU in the 0w40 grade. The RP filter is doing its job, but then its job is easy. New engine, top grade oils, there better be no crud in there! As for driving habits: everyday commute to work. At least 2 or 3 "fun blasts" per week. At least one long (1500 mile) highway trip on this OCI. I'm not easy on it, but I don't flog it at the track, either. Oil temps stay between 218 and 230F all the time.