Let's take a deeper look at one of the oldest and most controversial questions in the automotive kingdom: how often should you change your oil? It's an important question, because oil does a hell of a lot: it lubricates your pistons, bearings, chains, camshafts, cranks, kumquats (just kidding, that last one is a fruit) and is a vital part of your engine's cooling system. You gotta keep it up to snuff.
When your father and your father's father were growing up, 3,000 miles was the standard oil change interval, no questions asked. Then synthetic oil came into the picture, and some people changed their tune in favor of a 5,000 to 7,500 mile interval. Flash forward to today: some manufacturers in the US recommend 10,000 miles. Abroad, that occasionally climbs as high as 18,000 miles.
None of those are actually right. Because this timeless query has a surprisingly complex answer.