Are all STi aluminum control arms created equal?

[Over Engineering]

Ok, I have been looking all over for a definitive answer to my question. I am looking to upgrade my Forester's front control arms to aluminum, I have to do a ball joint anyway so while I have it apart I might as well upgrade right? My Forester is basically the same as a 07 WRX except the rear control arm mount which I will have to keep.

Anyone have an idea what years are different than other years? I would think they are all the same but I know there were subframe changes from 04 to 05.

Thanks!

 

[HolyCrapItsFast]

I know the GR's are different than the GD. All the GD's are the same but I'm not sure about the actual dimensions and geometry differences between the WRX and the STi. From what I can tell by looking at the manual they look like they are interchangeable.

You need a second opinion though. I'm not 100%

 

[Over Engineering]

Yeah, I figured they were all pretty much interchangeable (GD models only). I see a lot of conflicting information online. Some say the 05's are longer due to a track width increase of the 04's. Some say the 04's provide more castor as they are actually the Spec C control arms.

I will find out though, I got a good deal on some 05's. I won't be able to directly compare to another STi but I have alignment data on my Forester now and I will see what it ends up like after.

 

[STimedic]

It should just be the spindles(uprights) that provided the track width change on the 05-07, since they did the 5x114.3 then. Logic tells me that, but not 100%

 

[Over Engineering]

It should just be the spindles(uprights) that provided the track width change on the 05-07, since they did the 5x114.3 then. Logic tells me that, but not 100%

The track width change really shouldn't be in the spindles, that change would mess with the scrub radius in a bad way. In 05 they also changed the subframes a bit.

I do know that the 2004 control arm is a different subaru part number than the 05-07's.

 

[joey.lisano]

The 04-06 STI lower control arms are all the same. The 07 arms have 1.5* less caster.

The WRX has steel control arms that have as much caster as an 07 STI.

 

[frankensubie]

the main difference in track width up front is made up in the cradle the control arms are mounted to, caster changes can be made with an "anti lift kit" , out back the lateral links are longer than the gc (except in the wagons )