I pulled the trigger on the new T4 after my recent top-end rebuild. I figured they couldn't have drastically reformulated the original product, given the fact its a 15w designed for diesel engines and not strictly regulated like the 5w/10w designed for newer gasoline engines. I think diesel engine require the higher volume of zinc so its just a given that the numbers will be there. FWIW, my engine is running sweeter than ever so I don't think anyone will be surprised with the VOA when it finally hits the site.