Air / Transmission Filters Replacement

Air filter, pcv valve and cabin air filter: as needed
Change Transmission filter-30,000 miles, 90,000 and 150,000 miles

A slightly dirty filter actually cleans more efficiently than a brand new filter. That's because the debris trapped by the filter element helps screen out smaller particles that try to get through. But eventually every filter reaches the point where it causes enough of a pressure drop to restrict airflow. Fuel economy, performance and emissions begin to deteriorate and get progressively worse until the dirty filter is replaced.