service beyond owner's manual

A good way to interpret this, is that each service that is due at 15k, 30k, or 60k, will be due every 15k, 30k, or 60k with rare exception. It is worth noting, that each k service has a variety of inspection points that allow for other possible recommendations. Also, that as a vehicle ages, the interval does shorten up. Finally, mileage is the most important indicator in most service points, instead of months.