Before we get into this discussion about the best diesel fuel additives, it's important to understand exactly what diesel additives are. During the refining process, diesel fuel receives a rating ...

John Paul, AAA Northeast's Car Doctor, answers a question from a reader curious about using Marvel Mystery Oil. AP Photo/David Zalubowski ...

Winter is the time of year that really puts diesel trucks and tractors to the test. Sure, a boosted engine loves cold air, but you know what doesn’t? The fuel that makes these workhorses run. That’s ...