Improve your Subaru’s performance with the GrimmSpeed Air Oil Separator Red, designed specifically for 2002-2021 Subaru WRX STI, Forester XT, and Baja XT models. This premium AOS prevents oil from entering your intake system, ensuring cleaner combustion, better fuel efficiency, and reduced engine maintenance. It’s the ideal upgrade for enthusiasts seeking reliable, long-term protection without compromising factory PCV function.

Crafted from fully machined billet aluminum with a durable red anodized finish, this separator features a unique design that requires no mesh media or draining. It’s maintenance-free and uses user-replaceable O-ring seals for easy upkeep. The GrimmSpeed AOS effectively reduces knock risk, excessive oil consumption, and harmful emissions by removing oil from crankcase and head ventilation air.

Perfect for Subaru owners running factory-level blow-by, this compact, efficient separator is built to last and maintain itself automatically. Upgrade your Subaru WRX STI or Forester XT today and enjoy a cleaner, more efficient engine. Shop now at Subimods for expert parts and fast shipping.