All internal combustion engines use outside air to mix with fuel for combustion. This air must be very clean to prevent wear on precise engine components. All modern vehicles have filtering devises for this process. The Air Filter Element collects dirt, dust and pollen and stores it. It is designed to be replaceable. The life of an air filter element depends on the conditions a vehicle is operated in. If operated regularly in dusty areas the air filter element should be replaced more frequently. We recommend the air filter element be inspected after about 15000 miles of use and replaced if needed. It should be replaced at least every 30,000 miles.