I've got an 04 Forrester 2.5 XT. A while back I noticed a noise, sort of a muffled whine. I thought it to be from the new tires I has just purchased as they had a little more aggressive tread pattern than the previous tires. This muffled whine has turned into more of a muffled roar. Still sounds like mud tires only has gotten louder. I've changed the rear differential oil with no change. I'm thinking rear wheel bearing as it seems to be coming from the right side. I've changed wheel bearings on many American made cars and trucks, but not a Subaru. Any help with a different diagnosis and or dissassembly of the rear wheel hub would be helpful.