My '02 Outback Limited has reached the 60,000 mile mark and my '00 GT is reaching the 30,000 mile mark. Is it time to change the AT filter and the PCV valve? I recall from the shop manual that the AT filter is basically never changed. I believe the same note was made regarding the PCV. These two items are not mentioned on the Subaru maintenance schedule. The differential and AT fluids are only recommended to be "inspected" on a regular basis, not replaced. When should these actually be replaced?