I've been running the T6 Rotella for almost 115,000 miles with no noticeable wear on my engine (617) so far. Chain stretch on the one I put in 102k ago is .5 degrees, and still starts at 0F with a 5 year old battery, 15 year old starter, and no block heater....315k on engine.

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-diesel is not just a fuel, its a way of life-
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