I recently completed the Auto-RX treatment on my car, and filled with Mobil 1 0w-40 on my last change. I'm using more oil than ever! Does anyone have any stats on the new Mobil 1's volatility? I stopped using the TriSynthetic M1 because of its volatility, but I thought they'd licked it with the SuperSyn formulation. On a related note, I'm seriously considering moving to M1 15w-50 to stem the consumption. How low can I go (temp wise) seeing as it flows better than many conventional 5w-30 oils? I'm in Chicago, and we can see temps below 0.