nbuonaiuto

Engine Oil: 17mm or 11/16" socket

Front Differential oil: Torx V-70 hex-star driver

Rear Differential Oil: 10mm hex-Allen driver, and 3" extender for upper fill plug. Go easy, if you strip threads on plug the oil will slowly leak, new lower drain plug = $6 and new upper fill plug = $2. If you strip threads in holes on differential unit itself, you gotta buy that whole back cover piece for like $100 to restore. Both upper and lower plugs should fit in either hole, lower drain plug has magnet tho.

PCV valve: 3/4" Deep socket, and 6" extender. If you overtighten it don't go nuts trying to loosen back, the force you exert will probly break something else next to or beneath PCV valve.

KenLyns

Wish I had seen this post before I started replacing the rear diff fluid. Every guide I've seen (including a Youtube video on a 2009 2.5i) shows two plugs with 13mm square holes (which accepted a 1/2" drive breaker bar nicely). Looks like Subaru changed the rear diff cover design for 2011. Old plugs had pipe threads which called for thread sealant. New plugs are flanged, have straight threads and use a crush washer to seal. The new plugs appear identical to the design on Toyota trucks.