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  • GrimmSpeed [02-07 WRX / 04-21 STI] Air/Oil Separator | 078006
  • GrimmSpeed [02-07 WRX / 04-21 STI] Air/Oil Separator | 078006
  • GrimmSpeed [02-07 WRX / 04-21 STI] Air/Oil Separator | 078006
  • GrimmSpeed [02-07 WRX / 04-21 STI] Air/Oil Separator | 078006

GrimmSpeed

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Air/Oil Separator | 078006

Fits: 02-07 WRX / 04-21 STI

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$42600
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Auto Parts Store of the Year 2026

GrimmSpeed Air/Oil Separator | 078006
Fits: 02-07 WRX / 04-21 STI
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Fitment

Description

An Air/Oil Separator has one job, remove the oil from the Subaru STI engine ventilation system so the oil does not get sent through the intake system.

The GrimmSpeed Subaru Air/Oil Separator has a unique patent pending design that allows you to maintain your PCV Valve while separating the oil out of the crankcase and head ventilation air! Our AOS will allow your engine to run more efficiently due to the separation of oil from the intake system. When there is oil in your system, the result is 1) reduced fuel octane 2) higher chance of engine knock(detonation) 3) worse emissions 4) higher oil consumption. Our Subaru Air/Oil Separator will solve all of these problems. 

In typical GrimmSpeed'fashion, we have made a very compact unit that packs a powerful punch(and looks good while doing it)!

No more having to check/empty your catch can and refilling your oil. The GrimmSpeed AOS coalesces oil without using a mesh media. Mesh medias can cause contaminates to collect and build up resulting in possible sludge. Our AOS is self maintained so you can just sit back, stop worrying, and enjoy driving your car!

Few aftermarket accessory distributors guarantee the satisfaction we offer. With us, you are confident of superior quality, high performance, and durable air/oil separators.

Best Air/Oil Separator On The Market For Subarus

The GrimmSpeed Air Oil separator is an excellent choice for Subarus. It helps maintain the PCV valve and separate oil and air in the head ventilation. Its efficient air-oil separation helps minimize oil consumption, emissions, and detonation risks and boosts fuel octane.

While it has a compact design, the GrimmSpeed air oil separator is significantly robust. It coalesces oil without a mesh medium, meaning you do not need to empty the catch or refill the oil. This product goes beyond separating the vapors from the head.

You must buy the GrimmSpeed air oil separator from a reputable distributor. Fortunately, JDMuscle boasts incredible experience and knowledge in the field, making it easier to advise you on which option is suitable. Our excellent online reputation shows why we are your ideal partner.

Our experienced technicians will help diagnose AOS system issues and fix them. You can also rely on us to install the device. Besides our unmatched affordability, you can pay for your parts in four easy installments, avoiding strenuous burdens on yourself.

Get The Best Service

At JDMuscle, we assure you of genuine parts and accessories. We are certified distributors with unmatched knowledge of Subaru WRX and STI vehicles, assuring you of high performance. Visit our online store and choose a suitable GrimmSpeed air oil separator to improve the performance of your car.

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