Has the outside temperature gone up considerably since the new oil? It has here in the last few days, no more -20F weather. Ive noticed a few mpg increase both to work and back, as well as downstate.
I would just want to make sure that all things are near equal first. Since I too would not normally think that oil alone would make that much of a difference.
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Winter daily driver, parked most days right now
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Summer daily driver
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