tire rotation recommended every other oil change-6,000 miles. there's much discussion about cross rotating, or not. in my experience it doesn't make a difference, front to back is most simple, and if they're directional you have to do it that way anyway. if you want to rotate your spare in, you should probably cross, and add spare. you only have to cross one side, usually cross fronts, and move backs straight up. if everybody would just do it every 6k or so, they'd have a lot of luck with tires. my daily driver goes about 80-100k on tires till its time to replace them.