i'm gonna throw this link up for you guys to peruse . Don't know if it's really a legit test or if it's something underwritten by an oil company but they're saying that they got 14,000 miles out of Mobil One with one oil filter change along the way and topping up of course . They also tested Amsoil which did well also
http://neptune.spacebears.com/cars/s.../oil-life.html
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