Its generally good practice to replace the PCV valve at regular intervals as they can clog over time and cause oil leaks and other issues. I replaced the PCV valve on our 2015 Subaru Forester 2.5 during a 90k service. The factory service schedule doesn't have a replacement interval set for the PCV valve however the old valve was visibly junked up. You only need a 19MM socket with extension and a ratchet to change the valve out. The valve is pipe thread, which means the threads are tapered and it requires thread sealer. Also exercise caution when tightening the PCV valve, you don't want to strip out your engine block.
- Subaru Part #: 11810AA141