Hello everyone. I have a general question: Mobil 1, claims that there 15w-50 grade oil contains more of the supersyn formula, or additives, then the other viscosity grades. Would that make the 15w-50 a better choice in extended drain intervals? I have a 2.2l Ecotec, and i live in NY, would it be wise to run 15w-50? Or, should i just stick with the 5w-30?