Moroso Air Oil Separator

Part #: MOR 85484


MSRP: $406.64


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Brand: Moroso
Color: Silver
Installation Hardware Included: Yes
Material: Aluminum
Mfgr. Warranty: 90 Days
Return Policy:

RallySport Guarantee - 30 Days

Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.


Subaru Impreza
WRX STI 2004, 2005, 2006, 2007WRX STI Limited 2007WRX TR 2006, 2007WRX Limited 2006, 2007WRX 2006, 2007

From the factory excess crankcase vapors, residual oil and moisture are vented back into the intake manifold and crankcase ventilation system. This can coat the pistons and everything else with a detonation prone layer of oil. This is no good in a turbocharged vehicle.

Moroso has come up with a 2 tank system that allows the factory crankcase ventilation to operate how it was designed. No other system on the market does this.

Billet Aluminum bodies compliment any engine compartment and can be polished, chromed or powder coated for a custom look. Each Separator has a billet aluminum clamp, a bottom drain with an elbow that makes draining the collected oil a mess-free operation. Includes stainless steel mounting brackets, 1/2" inlet and outlet fittings, 66" of 3/8" diameter and 66" of 1/2" diameter rubber hose for plumbing the Air-Oil Separators inline.

This is for cars with a TMIC and stock location turbo. This kit is not designed to be used with a FMIC or rotated mount turbo.





  • AnswerQ: rotated mount turbo  sals7tmp30423 3 months ago

    What is it that causes this to not be able to be used with a rotated mount. If its a clearance issue, can this still function if the mounting location is changed even if it requires modifying the length of some of the hosing

    • A: This part will sit right above the stock turbo and the lines will be ran to the top mount intercooler. We cannot confirm if this will work if you modify the setup.

      Chris W. 3 months ago

  • AnswerQ: Capacity   konascrap05 6 months ago

    What is the oil capacity of this system before it needs emptied

    • A: The Moroso Large Body AOS tanks each hold approximately 8 fluid oz.

      Moroso Performance 6 months ago

  • AnswerQ: 05 WRX  RAWeiss9124717 1 year ago

    So ideally with the cruise control disconnected/removed this AOS should work on my 05 WRX? Theres no other specific fitment issues?

    • A: If the cruise control is removed, then this should work on your 2005 WRX. Unfortunately Moroso has not been able to guarantee this, but that is what we have found.

      Zach G. 1 year ago

  • AnswerQ: strut tower bars  AznCuddy 1 year ago

    Would the Cusco strut tower bar clear this product?

    • A: We have not fitted the Cusco strut tower bar with this product and have not had the ability to confirm fitment at this time.

      Nick S. 1 year ago

    • A: We Have not tried fitment with the Cusco Tower Brace at this time. I have looked at a few photos online and have a strong feeling it will clear as long as the cans are dropped down.

      Moroso Performance 1 year ago

  • AnswerQ: Grimmspeed Turbo Heat Shield  Richsta4249299 2 years ago

    Can you confirm fitment with a grimmspeed turbo heat shield.

    • A: We have not seen any issues with this AOS and an aftermarket heat shield.

      Spencer H. 2 years ago

    • A: I cannot at this time, It is designed to be used with an OEM heat shield. However it very well may fit.

      Moroso Performance 2 years ago