Your car doesn't *require synthetic* so dino oil is fine.
If your really worried do what I did and get an oil analysis.
http://www.subaruoutback.org/forums/89-oil-fuel-discussion/45346-2-5-12-oil-analysis.html
If your really worried do what I did and get an oil analysis.
http://www.subaruoutback.org/forums/89-oil-fuel-discussion/45346-2-5-12-oil-analysis.html