Are Subaru CV splines the same across models?

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k3rb3ros
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Are Subaru CV splines the same across models?

Post by k3rb3ros »

My Legacy SS I bought is a bit of a Franken car. It has STI hubs and brakes swapped on the front and and original wheel hubs with STI brakes (with adapter brackets) and rotors in the back. The unfortunate side effect of this being the parking brake doesn't work as the inner drum diameter for the STI brake rotors is larger then the maximum radius of the stock legacy parking brake shoes. When I bought the car the previous owner included 2 rear STI wheel hubs and said that swapping these onto the backs would fix the problem. While I think this is true I am worried that the splines in the legacy CVs won't match up with the splines in the STI wheel hubs. So before I take the car apart I want to figure out what I am getting myself into. Is swapping STI rear wheel hubs onto a Legacy SS a direct bolt on fitment or do I need to change or modify the rear CV axles? If so what parts do I need to make this work?
mike-tracy
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Re: Are Subaru CV splines the same across models?

Post by mike-tracy »

Subaru axle splines vary a bit between models. You can't use STI hubs and axles with a legacy diff,
or legacy axles and diff with STI hubs.

You can use STI diff, STI axles with STI hubs in the rear to use the rear parking brake. The downside is the STI uses longer axles due to wider track (both front and rear). So you have to compress the axles as much as possible. Reliability and longevity may (and probably will) be affected.

I've run in to this problem, and one option is to buy sti axles and custom axle races from subarudave (he has a website you can find through google) and make your own hybrid axles. This will let you use any r160 (IE. non sti diff) with sti hubs and brakes, and the hybrid axles. Then your 190mm STI parking brakes will work.

Or, you use the stock legacy hubs, axles and diff and keep the parking brake with legacy SS ventilated rear brakes & calipers.

If you ditch the fancy rear brakes for stock ventilated SS brakes, you'll save hundreds or $1000+, but the "bling factor" won't be there. All that for a functional parking brake. Silly subaru.


Here's what I'll be doing (until I obtain a complete rear STI axle/hub/rotor/caliper/diff setup) - 06/07 WRX 2-piston rear calipers & rotors with their adapter brackets, stock hubs, axles and diff. Still looks good, and considering the car uses the rear brakes only 10% of the time under most circumstances, i don't have the need to upgrade to rear brembos any time soon.
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote: Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
mike-tracy
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Re: Are Subaru CV splines the same across models?

Post by mike-tracy »

I remember reading years ago that you could buy the rear brembo rotors that had a 170mm parking brake hat. If they still make them, you'd be in business with just new rotors
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote: Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
jamal
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Re: Are Subaru CV splines the same across models?

Post by jamal »

Yeah. while the sti rear hubs do use slightly different bearings, getting the axles to work is a bit of a hassle. Up front the 5x100 hubs and bearings are no different from any other 5x100 subaru.

The two ways to do the rear brembos on the 170mm brake is either with taller shoes or the adapter rotor.

You have two options for rotors. The fancy DBA 4000, and then the KNS brakes plain version, also made by DBA

https://www.rallysportdirect.com/part/r ... ingle-rear
http://www.knsbrakes.com/c/caliper-seri ... ngle+Rotor

If you want a set of the DBA 4000s I carry them, and can get you a pair for less than in that link from rallysport, but it's still like 150 a piece plus maybe a bit for shipping (I can get you an exact price with a zip code), so the KBS route would be the cheaper way to go.
peter@functionauto.com
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