Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/27/21 10:22 p.m.

Who knows Subarus?

I'm installing a 2010 Legacy "split case" 6 speed transmission into my Vanagon (build thread to follow, probably when I get my cables). The engine is a frankenmotor, a naturally aspirated EJ25 with SOHC EJ22 heads. It's currently running the VW transmission.

What clutch do I use? I have the flywheel that came with the 1999 Outback-spec EJ25 (I hope). Do I just get the matching clutch for that, or do I get the clutch that matches the transmission? 

Streetwiseguy
Streetwiseguy MegaDork
12/27/21 11:25 p.m.

Worst case, you get the pressure plate and bearing for the flywheel, and the disc for the trans.

I figure there will be a kit to fit the engine/flywheel, and the input shaft on the trans is likely the correct spline count and size, you are golden.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/27/21 11:56 p.m.

Good point, I may (MAY) still have the original disc from the engine donor to check against the input shaft. I'll check that tomorrow.

nocones
nocones GRM+ Memberand UberDork
12/28/21 6:56 a.m.

I know it's not super definitive but the clutch alignment tool appears to basically be "Subaru All MT" since 1990.

https://www.levelultraproductgroup.com/product/advanced-clutch-alignment-tool-at90/

AnthonyGS (Forum Supporter)
AnthonyGS (Forum Supporter) GRM+ Memberand SuperDork
12/28/21 9:41 a.m.

I know the EJ25 and turbo 2.0 transmissions have a major difference:  Push vs pull clutch.  I'm pretty sure either will bolt up to one another too.  From what I've read, you need to match the clutch to the transmission type and use the appropriate flywheel.  
 

Knowing Subaru a little and how they love to use parts for a long time, your flywheel might be compatible already.  If you have the 6 speed clutch handy, I'd see if it will bolt onto the flywheel.

You could also take your flywheel to Subie recyclers in CO.  Heck you might just give them a call.  I would love to be closer to them to grab some things for my RS.  

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 9:51 a.m.

We're a long way from the old 2.0 turbo here :) Unfortunately, I don't have the 6 speed clutch or flywheel but the continuity of the alignment tool bodes very well. I might just pick up the clutch at Napa and take it from there.

Subie Recyclers is about 4 hours away when it's not storming in the passes, I'm not sure I'll stop by :) I do have a local Subaru specialist but they're all about 600 hp turbos and aren't terribly welcoming.

AnthonyGS (Forum Supporter)
AnthonyGS (Forum Supporter) GRM+ Memberand SuperDork
12/28/21 10:29 a.m.

In reply to Keith Tanner :

There are tons of Subarus in CO and Tacoma's from my visits.  
 

You could call Subie recyclers and 4 hrs isn't too bad.  I know traffic out your way from the Denver area can be rough these days.  In certain parts of TX, 4 hrs is a reasonable trip.  

I sometimes take 3.5 hrs one way to OKC just for good eats, but I know I'm unusual in that regard.  

Any local parts places or dealers that would have a flywheel and clutch you could compare (Napa idea seems promising)?  
 

I'd be concerned the 6 speeds are more like the turbo 5 spd transmissions than the NA 5 soda, since the 6 speeds first appeared in the STIs.  They may have NA and turbo versions of 6 spds too.  

Pete. (l33t FS)
Pete. (l33t FS) GRM+ Memberand MegaDork
12/28/21 12:06 p.m.

In reply to AnthonyGS (Forum Supporter) :

The split case 6 speed is NOT the STI 6 speed.  I forget its exact name.

Every one I have seen used a push clutch.  They also had the pilot bearing in the flywheel like a 5 speed.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 12:16 p.m.

I'm not driving 4 hours each way (realistically more like 5-6 in the middle of a snowstorm) to hassle some Subaru shop about which new clutch I should buy :) There are definitely loads of Subarus and Toyota trucks around here but unless they have dropped their clutch parts on the floor that's not much use to me. I'm not looking for a junkyard clutch, that's false economy in my book.
 

It is a push clutch iirc. And yes, very different from an STi 6 speed. It's basically a swollen version of the split case 5 from what I can tell.  

Looks like NAPA has the clutch in stock, I'll swing by and see if I can dig out that flywheel to match. Engine is still in the van for measurement purposes. 

Streetwiseguy
Streetwiseguy MegaDork
12/28/21 3:10 p.m.

A quick glance at the Luk catalogue suggests a 15-024 for a 2010 turbo, which has a 1" 24spline input shaft, 9 1/16 disc diameter.  The 99 Legacy is a 15-010, 1", 24 spline, 8 7/8 disc.  I don't see a description of the flywheel bolt pattern, and neither one has a radical step in the flywheel.  I'd go with the 99 clutch and flywheel, because 3/16 smaller disc diameter will make exactly no difference.  I cannot find a dimension of the release bearing, but the pictures look pretty generic.

Edit:  The release bearing is different.  Early car uses a 30502 AA150, late uses 30502 AA121.  the attachment to the clutch fork looks a bit different, but sizes are certainly similar.  The 150 bearing fits cars from 1990 to 2018, the 121 starts around 05 and goes to 17.

I'd still buy the 99 kit, but check the bearing/fork interface.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 4:33 p.m.

That's solid info, thank you. Is that Luk catalog publicly accessible? Sounds like a great resource. 

Of course, just before you posted that, I was at Napa picking up the 2010 clutch :) I think it might all come down to if I can find the 99 flywheel. If I have it, I'll get the clutch to match. If not, I'll get a 2010 flywheel.

I believe the clutch currently on the engine is some sort of weird hybrid for the VW trans, I seem to recall the flywheel looking aftermarket. 

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 5:27 p.m.

Found the 99 flywheel. Loads of room for a larger disc. But weirdly, the 2010 pressure plate bolt pattern is smaller than the bolt pattern on the flywheel. 

Back to Napa :)

Streetwiseguy
Streetwiseguy MegaDork
12/28/21 5:40 p.m.

If you can log onto a jobber store, all that info should be available.  Does Flyin Miata deal with any local jobbers?  If not, a friendly counterman can fix you up.

 

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 6:18 p.m.

We don't deal with any jobbers, no.

But what I did was bring the clutch fork and a couple of measurements with me this time. The 1999 Outback clutch does indeed have a larger bolt circle on the pressure plate, matching my measurements. And it's considerably cheaper, MSRP of $349 instead of $604 (we all know how NAPA MSRP works, I ended up paying about half that). Interestingly, the counter guy asked if it was "AWD, 4WD or FWD" which has me wondering if this clutch was used way back in the day when you could buy pushbutton 4WD Subarus as well as FWD ones.

The release bearing is different, but only in how it attaches to the clutch fork. The 1999 one uses a couple of clips for retention, the 2010 unit had a lip. But when I asked for a solo 2010 release bearing, it was the clip style that came up. Which makes me think the change is one to help with assembly line manufacturing more than anything else and the two are completely interchangeable.

Anyhow, now it's looking like I can use a full 5-speed 1999 clutch and flywheel on this 2010 6-speed. Which is good because that's a far more common piece of hardware so future parts availability looks promising. All I have to check now is the starter on that ring gear. Should have thought of that before...

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 7:15 p.m.

Starter good :) OK, I think I'll start a build thread for this thing. Just because.

Thanks for the help/support, everyone.

Pete. (l33t FS)
Pete. (l33t FS) GRM+ Memberand MegaDork
12/28/21 7:38 p.m.

There was also an "update" for the throwout bearing.  Subaru were having a lot of issues with the sleeve that it rides on galling, which would cause the throwout bearing to stay applied, which would melt the bearing.

and you would end up with a pressure plate that looks like this:

(This, IIRC, was on a 6 speed Crosstrek. Maybe Forester)

The fix is that pretty much all new throwout bearings have a larger ID than stock, and they come with a steel sleeve that you slip over the input after you scrape enough crud off of it for it to fit.  It secures with a set screw.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 7:58 p.m.

Well, poop. When I bought the clutch, there was an option for one that involved a sleeve:

  • Important Information:   Kit Contains Bearing Retainer Repair Sleeve and Matching Release Bearing. Release Bearing I.D. 35mm or 1.385 inches

I assumed that was for some sort of repair and with my shiny fresh trans I wouldn't need it. Are you saying I should take back this one and get the sleeved variant? They've got it in stock as well. My bearing has a 33mm ID and it will be riding on an aluminum surface, not steel.

Pete. (l33t FS)
Pete. (l33t FS) GRM+ Memberand MegaDork
12/28/21 8:05 p.m.

In reply to Keith Tanner :

Yes.  You really should.  Manual transmission Subarus are pretty uncommon around here and I've done several for this issue.

The bearing rides on aluminum, and while I do realize that you live in an automotive utopia where nothing corrodes ( smiley ) it's still a bad design.  Aluminum forms an oxide layer when exposed to air, and you're grinding the throwout bearing against that with every shift...

 

I am actually amazed that they give you the option.  Every replacement clutch I have seen comes with the larger OD bearing and sleeve.  I used to have a collection of sleeves from replacing clutches on vehicles that had already been repaired once early in life.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 8:14 p.m.

Maybe this was old stock and they were just happy to get rid of it :) Okay, one more trip to NAPA tomorrow. Thanks for the heads up. I've had enough aluminum...things gall and seize to want to avoid it. It will never be easier than right now.

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
12/28/21 9:16 p.m.

Mission accomplished. Straight swap and the sleeve is a perfect fit on the clean housing. Thanks again.

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