('03-'05) Which engine coolant? - Subaru Forester Owners Forum May 09, 2012The company that makes the anti-corrosion package for Subaru coolant also supplies Peak. That company has told Peak Subaru's anti-corrosion package is 100% compatible with Peak's. they are virtually interchangable. In a brilliant marketing move, Subaru has managed to skirt the Magnusson Moss Act but telling us to only use a "non-amine" coolant. Subaru Forester OE Engine Coolant - autozone Order Subaru Forester OE Engine Coolant online today. Free Same Day Store Pickup. Check out free battery charging and engine diagnostic testing while you are in store.