6MT Master Swap Thread

Best mod I ever did to my outback XT.

 

Loved it. And would never have gone back.

 

Sold my car for 16K.

 

Now driving my newer “Legacy”

 

13 WRX STI Hatchback.

 

My 5MT shifter boot to work on 6MT, mod;

http://legacygt.com/forums/showpost.php?p=1326375&postcount=76

 

I add my own "E" brake kill switch.

http://legacygt.com/forums/showpost.php?p=1376034&postcount=84

Best mod I ever did to my outback XT.

 

Loved it. And would never have gone back.

 

Sold my car for 16K.

 

Now driving my newer “Legacy”

 

13 WRX STI Hatchback.

 

Ain't that truth. Once I swapped 6MT into one of my LGTs, I had no choice but swap the other, too. Could not stand the 5MT anymore.

Undecided on a clutch. I really hate the idea of installing a used one and i think that i will be on the hairy-edge of the holding power of the oem unit. Im leaning towards either Exedy or South Bend, something with a full-face disk that’s rated for mid-400ish wtq.

 

Hammer- thanks for the links. I do plan on reusing my 5MT shift boots (Upper and lower) The iWire harness that I bought includes a jumper wire for the e-brake circuit to encourage the hoons.

FWIW, when I was researching my swap. If it wasn't drag/race car. Most keep the stock clutch, until they was around 500ftq. The 1st things to break are the axles.

OEM clutch, IIRC is built by exedy. IMO, for a DD, stock axle & clutch would be fine. For "race abuse", axles would be the 1st thing I upgrade.

Undecided on a clutch. I really hate the idea of installing a used one and i think that i will be on the hairy-edge of the holding power of the oem unit. Im leaning towards either Exedy or South Bend, something with a full-face disk that’s rated for mid-400ish wtq.

 

Other guys beat me but I echo them: Stay stock STI clutch!

 

What I read and understood was that tuned stock (VF52) STI turbo on E85 is totally fine. This is already a lot of torque so with sensible driving limit should be high up.

 

Anyway I strongly suggest first go stock and take a small risk that it won't work

Doing opposite and going "race" is very likely going to be pain in the neck on DD.

 

Failed clutch is not like some other component that is likely take other parts once it goes, so no reason to "play safe".

Regarding question if 6MT swap was worth it? Absolutely yes!

 

I originally didn't want to do it as it's a lot of money and 5MT should have been fine for (spirited) daily driver.

 

Due to problems with 5MT and stronger clutches on them I finally decided to put stop for that. To get strong stock clutch and transmission that should have no reliability issues. Diff locks and taller gearing were very tempting too.

 

What I didn't know was how ridiculously better and more engaging the gear shift is!

It's such a joy that it's nice to even sit in car and shift while engine is stopped

 

Other aspect I seriously underestimated is effect from proper diff locks. I've driven a lot of different, even somewhat sporty 4wd cars but never with proper locks in all diffs. I have suretrac front and rear. Centre diff is only visco (JDM Forester STI set up) but still great.

Tarmac capability is enhanced but on snow and ice it's just totally different car! Suddenly driver feels so much more skilled

Absolutely a blast on loose surface. Rear diff makes behavior predictable and front diff ensures that car pulls to direction streering is pointed. I'd like to have DCCD but I think it's more marginal and I desired tall gearing on 6th more for highway use. I drive primarily on highway and I've been really happy about it.

Front lsd is the biggest game changer.

New oem clutch, KB bushings, dccd switches have arrived at the house. I love it when parts start to pile up. The project feels real.

I now have everything that I need to complete the swap except for new bolts for the clutch/pp. however a new problem has come up - I no longer have access to the lift that I was going to use (my bro in law blew the motor in his F450 - we started pulling the cab off of it yesterday) who knows how long until it is available. Sooo - can I do this trans swap on jack stands? How high does the car need to be in order to clear the trans? Edited January 19, 2018 by Code

I now have everything that I need to complete the swap except for new bolts for the clutch/pp. however a new problem has come up - I no longer have access to the lift that I was going to use (my bro in law blew the motor in his F450 - we started pulling the cab off of it yesterday) who knows how long until it is available. Sooo - can I do this trans swap on jack stands? How high does the car need to be in order to clear the trans?

 

I lifted mine 24". Measured just behind the front wheels.

 

http://i99.photobucket.com/albums/l293/HAMMERDOWNGT/100_4303.jpg

Edited January 19, 2018 by HAMMER DOWN

Always did it on jack stands. Not a huge deal. But you need to get the car pretty high if you want the luxury of rolling the transmission in/out from under the car on a transmission jack. While 5MT is lightweight to do without, 6MT is a beast I cannot see lifting/dropping it without a jack.

So I did some searching but could not find an example of this set up.

 

Does anyone know if the JDM Forester STi trans and diff have the same dimensions as all other Subaru 6-Speeds? It seems like the perfect combination of Front LSD, Tall 5th and 6th gear, No DCCD. I just have not seen anyone used the SG9 drivetrain in their BP/BL chassis car.

 

I cannot find a USDM Spec-B drivetrain, but there are a few JDM Forester STi Trans @ Diffs on ebay. Has anyone ever attempted it?

Same case, will fit.

That's promising news. Has anyone seen it that could tell me all the axles/driveshaft/mounting points would be similar? Just wanted to make sure there wouldn't be too many curve balls with sourcing parts.

Driveshaft/axels will not fit. Different platform. Transmission will.

You'd need to keep your 5MT front axles for the 6MT box, and source LGT Spec B axles to fit the R180 rear diff... unless you're sourcing an R160 rear diff with the JDM Forester 6MT, then you've got everything you need for axles directly from your original 5MT bits pile.

 

Edit: Source either a Spec B rear drive shaft or the 4th Gen 4EAT rear drive shaft.

Edited January 24, 2018 by SBT

You'd need to keep your 5MT front axles for the 6MT box, and source LGT Spec B axles to fit the R180 rear diff... unless you're sourcing an R160 rear diff with the JDM Forester 6MT, then you've got everything you need for axles directly from your original 5MT bits pile.

 

He will still need Spec B driveshaft (or 4EAT driveshaft).

So I did some searching but could not find an example of this set up.

 

Does anyone know if the JDM Forester STi trans and diff have the same dimensions as all other Subaru 6-Speeds? It seems like the perfect combination of Front LSD, Tall 5th and 6th gear, No DCCD. I just have not seen anyone used the SG9 drivetrain in their BP/BL chassis car.

 

I cannot find a USDM Spec-B drivetrain, but there are a few JDM Forester STi Trans @ Diffs on ebay. Has anyone ever attempted it?

 

From everything I've researched, the SG9 is reserved for the JDM STI Forester and only the STI Forester (2004-2007, Rev C, D, E, and F).

 

Personally, I like the Suretrac Differential setups front and rear and would actually like to have this setup over the Spec B transmission. IIRC, Pre-2007 boxes should also have the oil pump in the transmission.

 

The JDM SG9 Forester 6MT trans for those years comprise three variations of 6MT transmissions and share only one (1) R180 Rear Diff. Rev D - 2004 and Rev E - 2005, share the same 6MT box

 

My previous post about axles would apply to any of these setups.

 

"C" TY856WL4CC (2004)

"D" TY856WL7CC (2005)

"E" TY856WL7CC (2006)

"F" TY856WL8CD (2007)

 

Code breakdown for the SG9 JDM STI Forester.

I have 2007 JDM STI Forester gearbox.

2004 STI drive shafts (5x100) at rear coupled to Hyundai Elantra CV-joints.

 

Highly recommended. Read my posts and ask if anything unclear.

 

4EAT prop shaft is ok, but must be OB to OB, or LGT to LGT

I have LGT shaft in OB and it's doable but needs spacers and longer bolts. No point to do it.

 

 

^this. Page 120 on this thread.

 

Parts for swap ordered. JDM STI Forester transmission and R180 diff. With axles/CV-jointes I'll try 5*110-STI/Hyundai -recipe.

 

Some good news from Russia for those, who want to get R180 on their B13 legacy but for some reason can't get Spec B axles.

 

We successfully installed R180 on 03' JDM legacy GT(B13 started from 2003 in japan), using pre-5*114 axles from 03' JDM GDB STI(30 splines on both ends of the inner shaft, AFAIK it's the same as US pre-5*114). We used outer CV joints from (you must get mentally ready) hyundai elantra. P/N MEYLE 37-14 498 0000. One car is running them with IHI VF42 for at least 50000 kms without faults, other just got them on.

 

Splines count:

LGT hub - 25

STI inner shaft - 30.

 

Swap is a direct bolt-on, CV joints went in as if they were manufactured for that exact reason.

Don't know the situation with parts in US, but here it's almost impossible to get your hands on used spec B axles, and for new ones you have to wait a month and pay ~$1200.

STI axles are easy to find wherever you want, and usual price is $300 for pair. Meyle CV's are $100 for pair and can be found in any shop.

 

 

So I did some searching but could not find an example of this set up.

 

Does anyone know if the JDM Forester STi trans and diff have the same dimensions as all other Subaru 6-Speeds? It seems like the perfect combination of Front LSD, Tall 5th and 6th gear, No DCCD. I just have not seen anyone used the SG9 drivetrain in their BP/BL chassis car.

 

I cannot find a USDM Spec-B drivetrain, but there are a few JDM Forester STi Trans @ Diffs on ebay. Has anyone ever attempted it?

I have 2007 JDM STI Forester gearbox.

2004 STI drive shafts (5x100) at rear coupled to Hyundai Elantra CV-joints.

 

Highly recommended. Read my posts and ask if anything unclear.

 

4EAT prop shaft is ok, but must be OB to OB, or LGT to LGT

I have LGT shaft in OB and it's doable but needs spacers and longer bolts. No point to do it.

 

Good point on the OBXT / LGT 4EAT driveshafts. It's been mentioned before and I should have remembered that.

 

Thank you for the link back to the STI/Hyundai hybrid axle shaft information. Good way to make our own if we can't source Spec Bizzle versions.

Not sure if a 2011 wrx Diff is able to be used in these or not but here is a cheap one on craigslist $75 https://houston.craigslist.org/pts/d/2011-subaru-impreza-wrx-parts/6452406868.html

Believe that is not an LSD given that the 2011 REX has only a VLCD and traction control (TCS).

SHTF at work so my swap has been put off until April.