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6MT Master Swap Thread


HAMMER DOWN

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  • 1 month later...

Hey all, so I've been scouring this thread and as many others I can find for a definitive list on the 5EAT > SpecB 6MT swap. I have a lead on the following:

 

Spec B 6MT

R180 diff (from spec B)

Spec B Axles

shift linkage

new flywheel (dual mass)

flywheel bolts

new clutch

clutch slave cylinder

shift fork

STi driveshaft (if needed) or LGT MT driveshaft

MT LGT ECU (if needed)

MT LGT pedal box

 

What else am I missing? I'm pulling this out of a LGT sedan and have access to almost everything from the donor car.

 

Anyone who's done this swap I could chat with?

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Dual mass is what the Legacy 3.0R Spec B (H6, 6MT) had (As far as I know). I believe USDM Legacy GT Spec Bs also had it.

 

Dual mass is heavier and smoother. So it's harder to stall the engine, and the car is smoother, but doesn't rev as fast. It's easier to drive for a road car.

 

Single mass is rougher, but will rev faster. So if you're building a car for drag racing, use a single mass. I believe the STIs use a single mass also.

 

They also make ultralight flywheels if you're racing.

 

Nope, USDM Spec B 6MT was single mass.

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Has anyone considered earlier MY STi 6MTs, not from the 04/05 STi. What challenges do you guys foresee if I try to perform a swap using the below transmission.

 

Transmission code - TY856WB1CA

Model range - JDM Impreza WRX STi MY01-02 + RA MY01

 

Final drive is 3.9, non-DCCD with AP Suretrac front and rear diff (R180)

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  • 4 weeks later...

I haven't had a chance to dig through the thread, but what's it take to fit a FA WRX 6mt into my wagon?

 

Looks like the FD is 4.11 which I believe means it'll pair nicely with my rear diff. I think I've heard it's basically a LGT 5mt with a highway gear.

 

Not too sharp on trans details except what I've taken apart in my time. Any insight or opinions?

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  • 1 month later...

Any reason a 6mt from a 2010 LGT wouldn't work for my '05 LGT wagon?

 

I'm currently running a 4.44 5mt from an outback, and acceleration is sweet, but 3400 RPM at 75 is getting old. I ran the numbers on the 2010 LGT 6mt and I should have similar 1-2 (higher gears and 4.11), but 6th would be 2700 RPM at 75 (which would be amazing).

 

I know there are "better" ones with LSD and such, but I'm not sure it's really worth it for how hard I push her. I've read through half this thread so far, but haven't seen the 2010 6mt mentioned yet so I thought I would ask.

 

I've read they are basically a 5mt + a sixth gear, still split case, but origins for the 6mt that was built for diesel torque, cable shifter...

Edited by Infosecdad
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Any reason a 6mt from a 2010 LGT wouldn't work for my '05 LGT wagon?

 

I'm currently running a 4.44 5mt from an outback, and acceleration is sweet, but 3400 RPM at 75 is getting old. I ran the numbers on the 2010 LGT 6mt and I should have similar 1-2 (higher gears and 4.11), but 6th would be 2700 RPM at 75 (which would be amazing).

 

I know there are "better" ones with LSD and such, but I'm not sure it's really worth it for how hard I push her. I've read through half this thread so far, but haven't seen the 2010 6mt mentioned yet so I thought I would ask.

 

I've read they are basically a 5mt + a sixth gear, still split case, but origins for the 6mt that was built for diesel torque, cable shifter...

 

 

We have 2010 Outback 6MT in the family. Did the clutch and headgaskets on it few years back.

 

 

BM/BR have different engine/tranny to body mounting design from BL/BP and older. On our cars the engine sits on the cradle and tranny gets bolted on to engine, tranny is also supported in the back by it's small cradle. On BM/BR it's the other way around - the tranny gets bolted to the body via it's own new design tranny mounts (similar approach to engine mounts in BL/BP), right in front of firewall. Then engine bolts on to tranny and engine is supported by a single engine mount in front, under the radiator.

 

 

Physically it looks different. I don't know if tranny mounts can be unbolted from the body of the transmission. If so then the tranny bell mouth looks similar/same to our transmissions to me. But then there is cable operated shifter to resolve.

 

 

Probably more trouble then it's worth.

2005 LGT Wagon Limited 6 MT RBP Stage 2 - 248K

2007 B9 Tribeca Limited DGM - 258K

SOLD - 2005 OB Limited 5 MT Silver - 245K

SOLD - 2010 OB 6 MT Silver - 205K

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We have 2010 Outback 6MT in the family. Did the clutch and headgaskets on it few years back.

 

 

BM/BR have different engine/tranny to body mounting design from BL/BP and older. On our cars the engine sits on the cradle and tranny gets bolted on to engine, tranny is also supported in the back by it's small cradle. On BM/BR it's the other way around - the tranny gets bolted to the body via it's own new design tranny mounts (similar approach to engine mounts in BL/BP), right in front of firewall. Then engine bolts on to tranny and engine is supported by a single engine mount in front, under the radiator.

 

 

Physically it looks different. I don't know if tranny mounts can be unbolted from the body of the transmission. If so then the tranny bell mouth looks similar/same to our transmissions to me. But then there is cable operated shifter to resolve.

 

 

Probably more trouble then it's worth.

 

Yeah, that's what I'm trying to figure out; if it's worth it.

 

I might be able to get a donor car for next to nothing (after I part out the other stuff), so I'm trying to do the research to see if it would work as I would have everything from the donor. So basically a free 6mt with all the parts needed, just happens to be a 5th gen LGT.

 

I'm not too worried about the cable shifter, it's more the mounts and driveshaft length. Looking at the parts catalog and pictures of the tranny, the bellhousing visually looks like it would align (it's connecting to a 255). And pictures that I've seen seem to show the ability to have a rear tranny mount like the 4th gens. I know the exhaust bracket is in a very different place, but that's fairly minor to solve.

 

For better or worse I'm drawn to challenges, so something slightly different like this kinda appeals to me (probably not in a good way).

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Looking at pictures and digging further, it seems like it's the same dimensions as the 5mt. Which would mean that my new driveshaft should work with it. Pictures of the underside look like it has the same tranny cradle as the 5mt. It's not the heavy 6mt of the STi or Spec B, but it has the nice tall gear (.666 x 4.11) for 6th that should help immensely on the hwy. I wonder if the Moore Blastplates would still fit as well... :-P

 

There is no pitch stop, but I could add one as the bolts are still in the same places.

I might be able to fit the blastplates, it looks like it might be possible.

The main concern at the moment is the wings on the bellhousing for the mounts on the 2010 that I don't need/use.

 

s-l1600.thumb.jpg.5a373bcbda795fb04c90aceb7a66159c.jpg

 

That "flange" on the upper left in the picture I'm fairly certain will get in the way of the traditional turbo location. But I think everything else will clear and work. So I need to debate if there is anything I can do with this or not.

Edited by Infosecdad
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Interesting. I still have my original 5MT and can take closeup pictures of the bellhousing if this is of any help to you.

 

 

EDIT: Also, IIRC the starter motor is different (I believe it looked much smaller).

2005 LGT Wagon Limited 6 MT RBP Stage 2 - 248K

2007 B9 Tribeca Limited DGM - 258K

SOLD - 2005 OB Limited 5 MT Silver - 245K

SOLD - 2010 OB 6 MT Silver - 205K

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Interesting. I still have my original 5MT and can take closeup pictures of the bellhousing if this is of any help to you.

 

 

EDIT: Also, IIRC the starter motor is different (I believe it looked much smaller).

 

Appreciate the offer, I have the wagon up on quickjacks to look at clearances, and I have a spare 5mt still connected to my original engine.

 

From what I can tell, there are two primary variants of the diesel 6mt; one is the more traditional 5mt case and the other has the big "wings" for the other style of "engine" mounts (that are actually to the tranny bellhousing) that is in the LGT 2010-2012. I like the idea of the diesel 6mt as the dimensions are the same as the 5mt so I could in theory use my front raxels and new driveshaft. It even uses the same clutch fork as the 5mt so I could use my hardened fork as well. It's theoretically possible to use my moore plates as well as it looks like the bolts are in the same locations. I'm running a 4.44 OBXT 5mt at the moment, so going to a 6mt w/ 4.11 would drop my RPMs at 75 mph by ~700, which is huge for me. MPG should go up and cruising road noise should go down.

 

I know the 2010-12 LGT 6mt are a split-case design, and it's a 5sp engineered with a 6th gear, and it's not as "strong" as an STi 6mt; but I'm around 300/300 and not planning to push more so it should be plenty strong.

 

I'm not worried about the cable shifter conversion, starter, etc. as I would be getting a full car to carry over parts as needed. I'm basically just looking at whether or not it would structurally damage the tranny to cut off that part of the mounting bracket so it would clear the turbo.

Edited by Infosecdad
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Infosecdad, so are you saying that you already have your hands on a diesel 6 mt trans?

 

Sorry, no. I'm looking at a 2010 LGT 6mt which is a variant of the diesel 6mt. If it doesn't work out, I may have talked myself into trying one anyway. I just like the idea of getting a full car so I have all the parts I need for the conversion (in theory).

 

I almost had a full Spec B to use, but was outbid by someone local :-P

Edited by Infosecdad
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Sorry, no. I'm looking at a 2010 LGT 6mt which is a variant of the diesel 6mt. If it doesn't work out, I may have talked myself into trying one anyway. I just like the idea of getting a full car so I have all the parts I need for the conversion (in theory).

 

I almost had a full Spec B to use, but was outbid by someone local :-P

At this time, I'm working on a 6mt swap from a 15+ WRX. Shifter is already installed, waiting on a throw out bearing to install the new to me trans.

 

Sent from my SM-G996U using Tapatalk

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At this time, I'm working on a 6mt swap from a 15+ WRX. Shifter is already installed, waiting on a throw out bearing to install the new to me trans.

 

Sent from my SM-G996U using Tapatalk

 

Is the shifter sitting a little bit higher due to the cable box?

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Is the shifter sitting a little bit higher due to the cable box?
Yes, the base is about ¼ higher itself. However the shifter itself is longer than even out stock one... I'll know more when I get the trans hooked up and in the car.

 

Sent from my SM-G996U using Tapatalk

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Trans is in. Driveshaft is in. So far with everything i was told and have seen has been accurate. I don't even have to change the shifter bezel! I have a ton of pictures, I will create a separate thread once I get the car back in the road.

 

Sent from my SM-G996U using Tapatalk

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