I should search before I ask, but my presidential campaign is eating up all my time. . . Has anyone done VOAs or UOAs on the yellow label stuff so we can tell for sure? I don't doubt that IF the yellow label DID comply with the higher A3 standard, and thus presumably perform "better," it would be marked A3. But I'd really like to see a scientific indication of just how much difference there really is in such things as viscosity stability, TBN retention, HT/HS vis, etc.