Depending on what kind of oil you use. Synthetic oil can go anywhere from 9000-25000 miles depending on which synthetic is being used and also driving conditions. Conventional oil can go anywhere from 3000-6000 also depending on the type of oil and driving conditions. Also if the car isn't being driven at least 3000 miles a year, it should be changed once a year. You'll never hear anyone say they changed their cars oil too much and it broke down.