How often should you change your synthetic oil in 2009 mazda 3?

For a 2009 Mazda 3 using synthetic oil, it's generally recommended to change the oil every 5,000 to 7,500 miles, depending on driving conditions and habits. If you frequently drive in severe conditions, such as stop-and-go traffic or extreme temperatures, you might consider changing it closer to the 5,000-mile mark. Always refer to the owner's manual for specific guidelines related to your vehicle.