2012 LGT 6mt into a 2005 LGT 5mt

[Infosecdad]

I've wanted to swap a 6mt into my '05 wagon since I got it, but the $4k+ price tag has prevented me from getting there. After a bunch of research on the 2010-2012 LGT 6mt I think I can figure out how to make it work.

 

From what I can tell, the 10-12 6mt is essentially the 5mt split case design that is redone internally to fit a 6th gear and was built for the EU diesel option. The 2015-2020 WRX 6mt looks to be a continued evolution of this design. These are different from the STi 6mt in that they are a split case design, cable operated, and not built as heavy. However, they were built to handle the diesel torque so I'm hoping it's plenty strong for 300-350 WHP.

 

A big plus for the spilt case 6mt is that it has the same dimensions as the 4th gen 5mt, so you can reuse most everything and should in theory only need the transmission and cable shifter. Everything else should be able to be transferred over. I believe that we can probably even use the 5mt blast plates and will try to prove that as part of my project.

 

I was looking at calculators online.

Here are the RPM differences at different speeds.

I used my 225/40/18 Pilot Sport All Season (25.2")

 

Stock 5mt (4.44) = 75mph @ 3276RPM <- Me currently with an outback 5mt

Stock 5mt (4.11) = 75mph @ 3033RPM

WRX/LGT 6mt (4.11) = 75mph @ 2737RPM (6th gear at .666)

 

It's about a 300 RPM reduction for most legacy 5mt, going to be almost 550RPM drop for me at 75mph from the outback 5mt. Something I'm seriously looking forward to as I'm making 4hr round trips to Vanderbilt pretty regularly right now.

 

OBXT 5mt (4.44):

1st - 3.166 = 30mph @ 5620 rpm

2nd - 1.882 = 45 mph @ 5015 rpm

3rd - 1.296 = 45 mph @ 3450 rpm

4th - .972 = 45 mph @ 2590 rpm

5th - .738 = 60 mph @ 2620 rpm

5th - .738 = 77 mph @ 3365 rpm

 

I'm struggling to get to 60 in 2nd right now as it's at 6685 rpm (I think my redline is 7k or 7.2k, I forget)

 

2012 LGT 6mt (4.11):

1st - 3.454 = 30mph @ 5678 rpm

2nd - 1.947 = 45 mph @ 4800 rpm

3rd - 1.296 = 45 mph @ 3200 rpm

4th - .972 = 45 mph @ 2400 rpm

5th - .780 = 60 mph @ 2560 rpm

6th - .666 = 77 mph @ 2810 rpm

 

I can still get to 60 in 2nd gear at 6400 rpm, so that's cool.

 

So I read that as I should keep a similar acceleration profile, but have a much, much better hwy cruising profile and mpg... We'll find out.

 

The unique issue with the 10-12 6mt is that it has a different mounting system for that generation with the main mounts actually on the bellhousing instead of under the engine like most other Subarus. I'm likely going to have to do some trimming on the upper passenger side mounting location to get the turbo and downpipe to clear.

 

What I have now:

Outback 5mt w/ 4.44 diff

Moore blastplates

Southbend Stg 2 clutch w/ 40k miles

Versus forged clutch fork

Clutch damper delete

Solid shifter bushings

Kartboy Shifter w/ 6mt Atlas knob

All kartboy tranny bushings

Driveshaft store driveshaft

Front Raxles

 

What I'm picking up that's needed:

2012 LGT 6mt (found on eBay for $425 + shipping)

2020 WRX shifter w/ cables 4k miles (picked up on eBay for $225)

 

What I'm picking up that's not needed, but wanted:

Perrin short throw adapter (Update: replaced the Perrin adapter with a weighted COBB adapter, much better)

1320 short shifter, gap remover, and brass bushing

Rear axle seals for my 4.11 diff that's been sitting for a couple years

Subaru Hi-Performance Gear Oil

Tranquil TSK3 sleeve and throwout bearing

 

I should be able to reuse my shift knob, clutch, fork, axles, driveshaft, and bushings.

I'm going see if the blastplates will fit.

Plan to document the work in images as I go.

I have to start teaching classes next week, so we'll see when I get a chance to actually get it all knocked out.

[SubOperator]

Do find out if TSK kit fits that tranny, they were model specific. Otherwise, great start and good luck!

[Pleides]

Sounded like the TSK kit fit the WRX FA20dit 6MT so I'd assume it would.

[Infosecdad]

Six Star Bernie lists the 2012 LGT 6mt for the TSK3 kit, so I think it should fit. (We'll find out)

 

https://sixstarbernie.com/i-23179111-pdm-tranquil-tsk3-case-saver-kit-subaru-wrx-impreza-forester-legacy-turbo.html

[JoeInOregon]

As an owner of an 05 I approve this .

 

Would love to do a 6mt one day without messing with the rear

 

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[KZJonny]

Subscribed to this one.

 

Seems like there is *massive* covid tax on 6MT's around me. They've probablty gone up 40% since last time I checked, or they're all out of stock.

 

I guess the JDM resellers are also having a hard time getting anything into seacans and shipped across the pond.

 

For the price of a trans from a destroyed rex and a cable shifter, this sound like a great option if it is relatively pain-free. At ~270 whp goal, I only really wanted a 6MT swap for the taller gearing, not because I need a bigger transmission.

 

Hope it goes well.

[Pleides]

Subscribed to this one.

 

Seems like there is *massive* covid tax on 6MT's around me. They've probablty gone up 40% since last time I checked, or they're all out of stock.

 

I guess the JDM resellers are also having a hard time getting anything into seacans and shipped across the pond.

 

For the price of a trans from a destroyed rex and a cable shifter, this sound like a great option if it is relatively pain-free. At ~270 whp goal, I only really wanted a 6MT swap for the taller gearing, not because I need a bigger transmission.

 

Hope it goes well.

 

I'm in much the same boat. Seems like some forum members here are getting crafty with alternative 6-speed options.

[Infosecdad]

Got the 2012 LGT 6mt today via freight as well as the WRX 2020 shifter mechanism.

 

 

6mt seems to be in good shape.

Will get her all cleaned up with new seals and such.

 

 

The 2020 shifter mechanism is so nice and smooth...

 

 

Even has STi stamped on it, which I found to be curious.

[k00laid83]

Nice! I'm keeping an eye on this build. I've been thinking of looking for a wrecked STI at an auction for a parts car. This really is cool to see as another option.

[NORULZleggy]

I will be following this also, but There is a reason why the 6MT from the 04 STI is king. I am not sure why you think 4K or more is high or a covid tax. I was told 5500 way before covid came. I had an 04 STI and the DCCD and all the other feature the drive train offer are worth me paying 5k.

[Pleides]

I will be following this also, but There is a reason why the 6MT from the 04 STI is king. I am not sure why you think 4K or more is high or a covid tax. I was told 5500 way before covid came. I had an 04 STI and the DCCD and all the other feature the drive train offer are worth me paying 5k.

 

A lot of us don't care about the durability of the gearbox or the DCCD. I actually DON'T want the DCCD because I don't want to get an aftermarket controller and have another item to break/put in the car. I don't plan to make my car a drag car or launch it. I don't need the durability of the STI trans. This swap is cheap and gives me what I want - a tall 6th gear for the highway.

[Infosecdad]

I will be following this also, but There is a reason why the 6MT from the 04 STI is king. I am not sure why you think 4K or more is high or a covid tax. I was told 5500 way before covid came. I had an 04 STI and the DCCD and all the other feature the drive train offer are worth me paying 5k.

 

Sorry, wasn't clear I guess.

 

$4k is about as cheap as I have found STi 6mt swaps, definitely find them in the $5-6k range often. If I was racing, wanted only the best, or had the disposable hobby income, I would totally go that route. It's the ideal state, and awesome for the people that can do it. But I'm working on a professor's salary with two kids in college; $5k for a 6th gear just won't happen.

 

However, I think there is another group of people that don't have the same level of needs/requirements that are more looking for something that can handle 250-350hp, have a taller 6th gear for hwy, and is closer to $1.5-2k in cost. I'm squarely in that group.

 

I get that doesn't work for everyone, but I don't think it's just one set of needs/requirements that should be applied to across the board. I mean you could argue no one should ever buy a WRX when an STi is there, and many people would, but there is still a good market for WRX.

Edited February 3, 2022 by Infosecdad

[shralp]

If this can be sussed out for a proper price I could totally see going this route for my '08 Outback stg.2 daily. It never seems too big a deal until I hop in my STI 6MT swapped track car and take it out on the highway. Then I'm reminded why I don't like the 5MT. The 6 speed is so much more sedate in the revs when you're just cruising. Might decide to push farther to 300HP to the wheels in this Outback one of these days but will never go farther. This would be a killer option for me.

[Febreze Mee]

Having not done any research in the "rear of the EJ motors" department, and pending that this fits, I too, would highly consider throwing in this 6spd swap for all of the reasons mentioned above for having this over and STi trans.

[KZJonny]

Sorry, wasn't clear I guess.

 

$4k is about as cheap as I have found STi 6mt swaps, definitely find them in the $5-6k range often. If I was racing, wanted only the best, or had the disposable hobby income, I would totally go that route. It's the ideal state, and awesome for the people that can do it. But I'm working on a professor's salary with two kids in college; $5k for a 6th gear just won't happen.

 

However, I think there is another group of people that don't have the same level of needs/requirements that are more looking for something that can handle 250-350hp, have a taller 6th gear for hwy, and is closer to $1.5-2k in cost. I'm squarely in that group.

 

I get that doesn't work for everyone, but I don't think it's just one set of needs/requirements that should be applied to across the board. I mean you could argue no one should ever buy a WRX when an STi is there, and many people would, but there is still a good market for WRX.

 

This.

 

Given infinite funds, sure, I would get an ex-STi trans as well. But I trashed my budget on the GT a long time ago, and still need to attend to the many things wrong with my Datto 510. Limited funds and too many projects..

 

~2K seems fairly reasonable for a box that will handle the power I intend to push though it, and bring down highway RPMs, etc... same story for many I am sure.

 

Completely agree that the ~4.5K JDM 6MTs go for, is totally worth it, if you are going to take advantage of it's features tho.

 

Really hope the install is hitch-free, for you and the rest of us who are interested...

 

I may have missed it above, but given that this is an adapted version of the LGT/Diesel 5MT with the extra gear in it, does that mean it is correctly splined for the existing axles and Gen 4 LGT propshaft?

[Infosecdad]

This.

...

 

I may have missed it above, but given that this is an adapted version of the LGT/Diesel 5MT with the extra gear in it, does that mean it is correctly splined for the existing axles and Gen 4 LGT propshaft?

 

I believe so, yes. That's what I plan to prove one way or another.

 

We know the 2015+ WRX 6mt does work with the 4th Gen axles and driveshaft, Scottydunno found that out recently.

 

https://legacygt.com/forums/showthread.php/15-wrx-6mt-into-05-09-legacy-ob-287486.html

 

I'm trying a similar idea with the 5th Gen LGT 6mt. I think the 2015+ WRX 6mt will be easier as it had similar engine/tranny mount setup, but I got my LGT 6mt a good bit less than any WRX 6mt I could find around me so I thought I would test it as well.

[Scottydunno]

I believe so, yes. That's what I plan to prove one way or another.

 

 

 

We know the 2015+ WRX 6mt does work with the 4th Gen axles and driveshaft, Scottydunno found that out recently.

 

 

 

https://legacygt.com/forums/showthread.php/15-wrx-6mt-into-05-09-legacy-ob-287486.html

 

 

 

I'm trying a similar idea with the 5th Gen LGT 6mt. I think the 2015+ WRX 6mt will be easier as it had similar engine/tranny mount setup, but I got my LGT 6mt a good bit less than any WRX 6mt I could find around me so I thought I would test it as well.

Thanx for the "honorable" mention. That case design is very strange.. it looks more robust at the bell housing area. If you can, can you please snap a picture of the inside of the crossover cable where it attaches to the shifter.

 

Soo... the TSK3 kit does infact fit the 15+ WRX 6mt. I have the snout piece from my old 5mt, couldn't find a replacement bearing back when I did my clutch before the swap.

 

The 15+ WRX 6mt case is exactly identical to our old 5mt. EVERYTHING bolts on to it like how it is on the 5mt. It's literally the last 3rd of the trans that's different. Axles spline properly, mounts line up properly. It's exactly as I described it, the easiest 6mt swap you'll do.

 

Here's a link to my thread in the transmission section.

 

https://r.tapatalk.com/shareLink/topic?url=https%3A%2F%2Flegacygt%2Ecom%2Fforums%2Fshowthread%2Ephp%3Ft%3D287486&share_tid=287486&share_fid=5383&share_type=t&link_source=app

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[Infosecdad]

Thanx for the "honorable" mention. That case design is very strange.. it looks more robust at the bell housing area. If you can, can you please snap a picture of the inside of the crossover cable where it attaches to the shifter.

 

Soo... the TSK3 kit does infact fit the 15+ WRX 6mt. I have the snout piece from my old 5mt, couldn't find a replacement bearing back when I did my clutch before the swap.

 

The 15+ WRX 6mt case is exactly identical to our old 5mt. EVERYTHING bolts on to it like how it is on the 5mt. It's literally the last 3rd of the trans that's different. Axles spline properly, mounts line up properly. It's exactly as I described it, the easiest 6mt swap you'll do.

 

Here's a link to my thread in the transmission section.

 

https://r.tapatalk.com/shareLink/topic?url=https%3A%2F%2Flegacygt%2Ecom%2Fforums%2Fshowthread%2Ephp%3Ft%3D287486&share_tid=287486&share_fid=5383&share_type=t&link_source=app

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Yeah, the case is different due to the mounting system in the 5th Gen LGT.

I'm curious if it helps the rigidity of the case, it seems like it should.

 

Here are a couple pictures of the cables that attach to the shifter, let me know if there is something specific you would like highlighted or focused. Which one popped off on you?

 

 

 

It's a shifter from a 2020 WRX with 4k miles, so hopefully is still fairly minty...

 

You can get replacement bearings from Six Star Bernie if you need to find one in the future.

https://sixstarbernie.com/c-1171180-oem-clutch-forks-pdm-case-saver-kits.html

[Zac88]

Following this closely

[Scottydunno]

Yeah, the case is different due to the mounting system in the 5th Gen LGT.

 

I'm curious if it helps the rigidity of the case, it seems like it should.

 

 

 

Here are a couple pictures of the cables that attach to the shifter, let me know if there is something specific you would like highlighted or focused. Which one popped off on you?

 

 

 

[ATTACH]295094[/ATTACH]

 

 

 

[ATTACH]295095[/ATTACH]

 

 

 

It's a shifter from a 2020 WRX with 4k miles, so hopefully is still fairly minty...

 

 

 

You can get replacement bearings from Six Star Bernie if you need to find one in the future.

 

https://sixstarbernie.com/c-1171180-oem-clutch-forks-pdm-case-saver-kits.html

The black ended cable is the one I had an issue with. It doesn't look like that. Mines from a 15, must be a design change. Mine looks like a plastic ball socket with a bushing inside. The bushing inside mine doesn't seem right to me hence the question and probably the source of my issue. Can you also snap a picture if the end of the shifter where that black end attaches? I wonder if that's different too. From what reading I've done, it looks like it's a 15-17 then 18-20 split as far as parts go.

 

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[Infosecdad]

The black ended cable is the one I had an issue with. It doesn't look like that. Mines from a 15, must be a design change. Mine looks like a plastic ball socket with a bushing inside. The bushing inside mine doesn't seem right to me hence the question and probably the source of my issue. Can you also snap a picture if the end of the shifter where that black end attaches? I wonder if that's different too. From what reading I've done, it looks like it's a 15-17 then 18-20 split as far as parts go.

 

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Here you go...

 

 

This looks like what you are describing...

 

That's the end that is supposed to go to the transmission. Any chance the cable was installed backward?

 

I looked up the cable part number and it's the same for the WRX 2015-2022, even dates back to the 5th Gen LGT 6mt.

https://parts.subaru.com/p/Subaru_2020_WRX-20L-6MT-Limited/Manual-Transmission-Shift-Cable/49246441/35060SC050.html

[Scottydunno]

Here you go...

 

[ATTACH]295100[/ATTACH]

 

 

 

 

 

This looks like what you are describing...

 

[ATTACH]295101[/ATTACH]

 

 

 

That's the end that is supposed to go to the transmission. Any chance the cable was installed backward?

 

 

 

I looked up the cable part number and it's the same for the WRX 2015-2022, even dates back to the 5th Gen LGT 6mt.

 

https://parts.subaru.com/p/Subaru_2020_WRX-20L-6MT-Limited/Manual-Transmission-Shift-Cable/49246441/35060SC050.html

Impossible to install backwards. The shifter is exact same as mine. Must be a design change on the cable end. Of course I didn't take any pictures of my shifter stuff.. =/

 

Thanx though! I'll be stopping at my local subaru dealership and be asking questions..

 

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[Infosecdad]

Impossible to install backwards. The shifter is exact same as mine. Must be a design change on the cable end. Of course I didn't take any pictures of my shifter stuff.. =/

 

Thanx though! I'll be stopping at my local subaru dealership and be asking questions..

 

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What's the other end of your cable look like at the transmission?

 

Looking at the cable, I think it could actually be installed backward, the clips look to be the same type and distance from the ends. I only ask because according to the subaru parts catalog this cable has been the same for 10 years now. (But they have been wrong before )

[Scottydunno]

What's the other end of your cable look like at the transmission?

 

Looking at the cable, I think it could actually be installed backward, the clips look to be the same type and distance from the ends. I only ask because according to the subaru parts catalog this cable has been the same for 10 years now. (But they have been wrong before [emoji38])

They look identical to yours except that one end. The reason I say impossible to put on backwards is because of the rubber accordian boots at the end. Those are always on the outside. I went to the dealer, I have to buy a whole new cable, they don't sell just end piece. I also forgot to ask about the cable adjustment procedure.. SMH

 

I looked up the cable everywhere else and that one end is the same as yours. It must be a design update and just never changed the P/N. When I get the new cable installed I'll take pics of the one I have.

 

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[Infosecdad]

Cut off the engine mount brace from the bellhousing, so that the turbo and downpipe will fit.

 

 

There simply isn't much clearance at all between the turbo and the bellhousing, and the 5th Gen LGT uses a different 4-point engine/tranny mount system because of the low, front mount turbo. The driver's side should have plenty of clearance, there isn't anything really hanging out over there below the starter. But, on the passenger side, it needs to be trimmed to not hit the turbo/downpipe.

 

This is one of the reasons (aside from being older) that the 2015+ WRX 6mt is an easier fit for the 4th gens, but the 5th LGT 6mt are cheaper that I've found.

 

I also moved over the pitch stop mount and sensors from my original 5mt. Just doing a few slow things while I wait for the starter (mine is throwing a code every now and then) and gasket set.

Edited February 6, 2022 by Infosecdad