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Resource: Subaru CV Axle Database

While researching for a potential modification (making hybrid axles), I found it very difficult to get good information on OEM Subaru CV axles. Most of the info was scattered across various forums and even then it was inconsistent. So to make heads or tails of this information I decided to put it into a table.

I will update this table as I find new information.

Cliff Notes

Starting with GD chassis, WRX rear axles (aka – 5×100/R160) have 24/25 spline rear axles. The GR chassis switched to bolt-in bearings with 27 splines so the GR WRX (08-14) has 27/25 rear axles. All STIs as far as I can tell have 27/27 rear axles. The LGT Spec B with the R180 has unique 25/27 rear axles.

YearModelAxle LocationOuter CV Joint Splines (Hub)Inner CV Joint Splines (Trans/Diff)Shaft SizeShaft Spline Count
(Outer/Inner)*		Axle LengthSource
1999ForesterRear242523mm#5
2000-2002RSRear242523mm#1
2001Legacy Outback
2002-2005WRX (Sedan)Front27—28mm29?#1, #7
2002-2005WRXRear242524mm21 or 22
2004STIFront2727
2004STIRear272730/30#6
2005-2007STIFront272729?/30
2005-2007STIRear2727
2006-2007WRXFront2725#1
2006-2007WRXRear242528
2008-2014WRXFront27
2008-2014WRXRear272528?#3
2008-
2014		STIFront2727
2015-202XSTIRear2727
2004FXTRear242522#4
2006-2009LGT Spec BRear2527
*Shaft spline count is very inconsistent and can vary greatly within the same model year.

Sources

  1. https://forums.nasioc.com/forums/showthread.php?t=367808
  2. http://wordpress.suberdave.com/?page_id=275
  3. https://www.wrxforums.com/threads/r180-into-08-wrx.23397/
  4. https://forums.nasioc.com/forums/showthread.php?t=2048240&page=8
  5. https://forums.nasioc.com/forums/showpost.php?p=3969011&postcount=2
  6. https://forums.hybridz.org/topic/73182-subaru-sti-r180-differential-and-axle-conversion-revised/
  7. https://thefactoryfiveforum.com/showthread.php?11112-Internal-CV-Spline-Mismatch

10 responses to “Resource: Subaru CV Axle Database”

  1. Jake Avatar
    Jake

    I built hybrid axles for one of my wagons so I could run an r180 with 5×100 4pot/2pots. I combined 22 spline 04-05 wrx rear axles with 06 STI inner cups using Suberdave inner races.
    I had to buy a bunch of donor axles before I found some with the correct shaft spline count. Two sets I purchased were definitely oem from bugeye wrx cars and the axle shafts had 21 splines.

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    1. A.A.Smith Avatar
      A.A.Smith

      I appreciate the info. I might need to do something similar fairly soon.

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  2. Em. K. Avatar
    Em. K.

    Hey guys, asking a question in regards to this thread and similar build. I’ve spent at least a month, searching vigorously for an answer and have came up short… Long story short, my 07′ WRX GD wagon was purchased with a JDM 02′ non-dccd 6 speed. Front diff. is 3.9, Center 1.0:1, Rear currently is 3.7. I purchased a “Code B2” 13′ rear open diff. with a 3.9 final drive. Upon installing, the diff.’s side gear spline counts is 25 and my wrx hubs are 27. Stock rear axle shafts are 27/27 inner and outer. The diameter is similar but the spline counts prevents installation. Any info on inner/out 25/27 splined rear axle shafts that can work with the 3.9 r160 installed into a gd wrx wagon? Thank you all in advance! 

    2007 WRX Wagon rear cv axle spline count: 27/27 inner and outer. I’m in need of 25/27 inner and outer with the right length and axle diameter.

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    1. A.A.Smith Avatar
      A.A.Smith

      It sounds like your car already had an R180 swapped and you tried to put an R160 diff in to get the matching final drive (FD) ratios. If that is the case, I would find a 3.9 FD R180 and use the axles/hubs you already have. Honestly, it may be easier/cheaper to swap the transfer gear to 1.1:1 and keep the R180. The rear GD chassis is a PITA to get sorted out with mix and match parts. I am still waiting to swap my R180 in with almost the opposite problem.

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  3. Em. K. Avatar
    Em. K.

    Thanks for the response… Both rear diff. units that I’m changing between are R160’s. Currently installed & oem diff. in the wagon being the 3.7 FD LSD and the replacement I picked up to install being the 3.9 FD, from a 2013 WRX. I’m sticking with the R160 platform at this time to keep most if not all of the current components/parts intact. Axle lengths seemed similar though I couldn’t fully seat the axle in the replacement diff.

    I’ve read info on the axles being different lengths in the narrow (08′-10′) and wide body (11′-14′) options but haven’t found a legit answer nor solution.

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    1. A.A.Smith Avatar
      A.A.Smith

      Ah, gotcha.

      That is weird. The only R160 I know of that run different rear axles are those JDM R160s with an cLSD.

      I remember GR WRX guys swapping vLSD R160s into their 08-14 WRXs. I don’t remember there being any issues with the axles, but that was a while ago.

      AFAIK, Subaru used the same 5×100 rear wheel hub for all WRX, Impreza, Outback, and etc models. The Legacy might be different as it always had an oddball rear suspension setup. The STI 5×114 rear hub is substantially bigger and it is where the STI gets its additional width from. In other words, the narrow body and widebody GR WRXs should have the same length rear axles. The spline counts should match what you are looking for (25/27), but they *might* be too long for your GD wagon. If the WRX didn’t have the dumb 24 spline hubs I would have tried the GR WRX axles by now. lol.

      Narrowbody/widebody axle info
      https://forums.nasioc.com/forums/showthread.php?t=2838579

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  4. Michael Lee Avatar
    Michael Lee

    does anyone know the spline count it the svx axles? I’m trying to swap 5×114.3 07 sti hubs on a 02 wrx. I know you can use an r180 but I was hoping to avoid that due to cost thanks.

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    1. A.A.Smith Avatar
      A.A.Smith

      I was curious about this so I did some digging. It looks like the SVX CV hub splines are 27 count, and the diff side is 25 (R160). This might work for you, however, I think the length might be an issue. One side has a weird double spline setup, so you will need two on one side. See the link below.

      https://www.ebay.com/itm/326855599186?

      The GR (maybe VA too) WRX is the only other OEM setup I am aware of at this time that has 27/25 rear axles. They also might be too long for a GD.

      Also, I did run into some misinfo about the SVX running a R180. Apparently, that is not true. Which makes since considering the diff side spline count. Scroll down to oppositelock’s post in the link below.
      https://www.subaru-svx.net/forum/archive/index.php/t-15017.html

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  5. bozac698 Avatar
    bozac698

    What I’d like to find out is whats the shaft length or inboard CV cup depth between a 2004-2005 WRX sedan and wagon.

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    1. A.A.Smith Avatar
      A.A.Smith

      Sometimes RockAuto lists the shaft lengths in the description.

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