See only parts compatible with your vehicle

    Air Oil Separators

    If you drive a Subaru, then it is common to see so many of them with some sort of aftermarket Air Oil Separator kit on it. The way the  stock PCV system on the Subaru works is that you have vents that come off the head, as well as the crankcase. These vents are routed to the turbo inlet, and even though inlet sucks in air, it can be common for oil to make its way into the inlet as well. Although this is somewhat a normal occurrence for a Subaru, burning oil can cause issues such as detonation, and it can effect the octane rating in your fuel. 

    Ar RallySport Direct, we carry a wide selection of Air oil Separators designed to filter the oil from the air, and drops the oil back into the oil pan so that only air gets back to the turbo inlet. You can choose one of Grimspeed's compact units that are mounted on the oil filler cap, or choose from other quality designs from Crawford, PERRIN, Beatrush and finally Moroso. 

    Now you can promote better longevity and a cleaner, healthier running engine with one of these fine products. And when you're ready to ready take control of your oiling system, choose a deeper oil pan  to increase the capacity, or get a catch can to catch any oil that overflows from your cranking system. 

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    63 Results

    GrimmSpeed Air Oil Separator Red - 2002-2007 Subaru WRX / 2004-2021 STI

    13 In Stock

    078006R

    GrimmSpeed Air Oil Separator Red - 2002-2007 Subaru WRX / 2004-2021 STI

    5.0(1)
    $315.00
    Killer B Motorsport Air Oil Separator Complete Kit - 2002-2007 Subaru WRX / STI

    GD-MV3S-C

    Killer B Motorsport Air Oil Separator Complete Kit - 2002-2007 Subaru WRX / STI

    5.0(2)
    $505.48
    COBB Tuning Air Oil Separator Black/Red - Subaru Models (inc. 2008-2020 STI / 2008-2014 WRX)

    46 In Stock

    822615

    COBB Tuning Air Oil Separator Black/Red - Subaru Models (inc. 2008-2020 STI / 2008-2014 WRX)

    4.5(2)
    $595.00
    PERRIN Air Oil Separator Red Stock TMIC - 2002-2007 Subaru WRX / STI

    3 In Stock

    PSP-ENG-605RD

    PERRIN Air Oil Separator Red Stock TMIC - 2002-2007 Subaru WRX / STI

    4.2(6)
    $622.13
    Killer B Motorsport Air Oil Separator - 2008-2014 Subaru WRX / 2015-2021 STI / 2005-2009 Legacy GT

    GR-MV3S-C

    Killer B Motorsport Air Oil Separator - 2008-2014 Subaru WRX / 2015-2021 STI / 2005-2009 Legacy GT

    3.0(1)
    $505.00
    IAG Air Oil Separator Street to Competition Series Conversion Kit - 2015-2021 Subaru WRX

    IAG-ENG-7211

    IAG Air Oil Separator Street to Competition Series Conversion Kit - 2015-2021 Subaru WRX

    4.0(1)
    $114.70
    IAG AOS Pitch Mount Bracket - Subaru Models (inc. 2004-2007 STI / 2006-2007 WRX)

    IAG-ENG-7802

    IAG AOS Pitch Mount Bracket - Subaru Models (inc. 2004-2007 STI / 2006-2007 WRX)

    4.0(1)
    $69.99
    Verus Engineering Air Oil Separator Automatic Drainback Kit - 2013-2021 Scion FR-S / Subaru BRZ / Toyota 86

    A0010A

    Verus Engineering Air Oil Separator Automatic Drainback Kit - 2013-2021 Scion FR-S / Subaru BRZ / Toyota 86

    2.0(1)
    $49.95
    IAG Performance V4 Air Oil Separator AOS - Red - 2004-2007 Subaru STI / 2006-2007 WRX

    IAG-ENG-7185RD

    IAG Performance V4 Air Oil Separator AOS - Red - 2004-2007 Subaru STI / 2006-2007 WRX

    $499.99
    IAG Performance Air Oil Separator AOS - Neon Yellow - 2015-2021 Subaru WRX / 2014-2018 Forester XT

    IAG-ENG-7187NY

    IAG Performance Air Oil Separator AOS - Neon Yellow - 2015-2021 Subaru WRX / 2014-2018 Forester XT

    $586.28
    PERRIN Air Oil Separator Neon Yellow - Subaru Models (inc. 2008-2014 WRX)

    PSP-ENG-606NY

    PERRIN Air Oil Separator Neon Yellow - Subaru Models (inc. 2008-2014 WRX)

    $622.13
    PERRIN Air Oil Separator Kit Black Wrinkle Finish - 2015-2021 Subaru WRX

    1 In Stock

    PSP-ENG-609BK

    PERRIN Air Oil Separator Kit Black Wrinkle Finish - 2015-2021 Subaru WRX

    $639.53
    Radium Air Oil Separator Return Kit (AOS-R Kit) - 2013-2016 Scion FR-S / 2013-2020 Subaru BRZ / 2017-2020 Toyota 86

    3 In Stock

    20-0351

    Radium Air Oil Separator Return Kit (AOS-R Kit) - 2013-2016 Scion FR-S / 2013-2020 Subaru BRZ / 2017-2020 Toyota 86

    $427.45
    02-07 WRX / 04-21 STI GrimmSpeed Air Oil Separator

    24 In Stock

    078006

    02-07 WRX / 04-21 STI GrimmSpeed Air Oil Separator

    $315.00
    COBB Tuning Air Oil Separator Black/Red - 2002-2007 Subaru WRX / 2004-2007 STI

    13 In Stock

    811615

    COBB Tuning Air Oil Separator Black/Red - 2002-2007 Subaru WRX / 2004-2007 STI

    $565.00
    08-14 WRX / 05-12 Legacy GT GrimmSpeed Air Oil Separator

    14 In Stock

    078016

    08-14 WRX / 05-12 Legacy GT GrimmSpeed Air Oil Separator

    $315.00
    Verus Air Oil Separator (AOS) - Blue - 2022-2024 Subaru WRX (VB)

    A0482A-BLU

    Verus Air Oil Separator (AOS) - Blue - 2022-2024 Subaru WRX (VB)

    $389.95
    Killer B Motorsport Air Oil Separator Barebones Kit - 2008-2021 Subaru STI / 2008-2014 WRX

    GR-MV3S-B

    Killer B Motorsport Air Oil Separator Barebones Kit - 2008-2021 Subaru STI / 2008-2014 WRX

    $359.00
    PERRIN Air Oil Separator Red Aftermarket FMIC - Subaru Models (inc. 2002-2014 WRX / 2008-2021 STI)

    2 In Stock

    PSP-ENG-607RD

    PERRIN Air Oil Separator Red Aftermarket FMIC - Subaru Models (inc. 2002-2014 WRX / 2008-2021 STI)

    $622.13
    Verus AOS Kit, Anodized Blue - 205-2021 WRX / STI

    1 In Stock

    A0323A-BLU

    Verus AOS Kit, Anodized Blue - 205-2021 WRX / STI

    $389.95

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    Whiteline Rear Diff Positive Power Kit Inserts - 2008-2014 Subaru WRX / STI / 2009-2013 Forester / 2010-2013 Legacy

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    Invidia N1 Dual Exit Cat Back Exhaust - Titanium Tips - 2008-2014 Subaru STI Hatchback / 2011-2014 WRX Hatchback

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    APR Performance Carbon Fiber Alternator Cover - 2015-2021 Subaru WRX / STI / 2008-2014 Impreza

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    APR Performance Carbon Fiber Alternator Cover - 2015-2021 Subaru WRX / STI / 2008-2014 Impreza

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    PERRIN Master Cylinder Brace Red - Subaru Models (inc. 2008-2014 WRX)

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    COBB Tuning License Plate Delete - 2002-2005 Subaru WRX / STI

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    GSC Power-Division Single Beehive Valve Spring Set w/ Titanium Retainers - Subaru Models (inc. 2002-2014 WRX / 2004-2021 STI)

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    Pedders Front Right Strut - 2002-2014 Subaru WRX / 2004 STI

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