Grimmspeed Aos 02-07 STi/Wrx 04-08 Fxt. Where does your oil go...?

Hey!.... And welcome to #modmonday . Today on the chopping block is the @Grimmspeed AOS unit for GD chassis Subarus and 04-08 Fxts. My AOS was on my STi for 2 years and then removed placed on my Forester.

The Grimmspeed AOS(Air oil separator) includes the hoses you see in the picture and the baffled cap that takes place of your oil cap. Now instead of oil being pushed into the intake tract and ingested by your engine you will have it returned right back home to the oil pan.

This is very helpful to keeping your intake tract clean of oil, keeping oil out of the combustion chamber (detonation) which also helps keep the octane levels at their peak numbers. And it takes away the mess of emptying a catch can.

One issue for those living in colder climates and taking short trips is condensation building up and going back into the filler neck.

This was originally installed on the STi and was great for daily driving and spirited back roads. It was a terrific fit for the car until I started auto-crossing heavily. Which under very hard extended turns you can push oil back through the AOS. Thus it was gifted to the 4Runter.

On the 4Runter it is an excellent fit for what the vehicle does. Helps preserve the engine and keep the oil where it should be. It has been on there for the last 2 years with slight condensation issues but this is due to my driving habits. Many cold weather starts and frequent short trips.

Questions, comments, thoughts? Leave them below!

Amazon link: Grimmspeed Aos