Jump to content

What 5MT transmissions fit 05 Legacy


Recommended Posts

Ok guys I have been doing alot of research on what 5MT transmissions fit into my 05 Legacy GT. I have 131k on mine (original), gears are a little notchy and I am getting a bearing howl on deceleration in gear (probably center diff bearings). I am also probably going to do a new clutch and TSK3 upgrade kit as well.

Looking to try and spend under 2k for a newer, low mileage transmission. I do not want a 6MT.


-So what transmissions from different (newer) models fit.

-Legacy or WRX?

-Will it be a direct swap?

-CV shafts, drive shaft, and shifter needed from that year?

-Rear diff needed from that year? I know wrx is different.


Also my Legacy's clutch pedal throw is very, very heavy. I have been fighting it since I purchased it, installed new clutch master, slave cylinder, steel braided line. Some days if I drive it around town for a few hours, by the end of the day my foot will start cramping and sore by the end of the day. It takes alot of leg hold down pressure to keep it down waiting for the light to turn green, mostly just take it out of gear now. Sometimes it doesnt like to go into first from a stop. Just doesnt seem right. I am a very conservative driver and drive mostly highway with little abuse on my car. I do have alot of upgrades but rarely WOT.


I've also contemplated on swapping clutch and pedal assembles just to see if that would help, from a newer wrx. I test drove a 2014 wrx the other day and it was at least 50% less stiff. <Can this be done?


I love my legacy and I am just not ready to give up on her for a 30k newer subaru. Any input would help. Thanks

Link to comment
Share on other sites

  • 1 year later...

I was looking for the same info, too bad there wasn't much information here. So I did a bit of armchair research.


In my case, I have an '05 LGT and the 5MT has been acting weird for far too long (some kind of bearing issues). I had finally convinced myself that I'm going to pull the transmission myself, but I'm not confident that I'll be able to easily diagnose the issue (and even more so if it's an internal bearing issue).


I wanted to find a compatible 5MT with the intention of swapping. Additionally I feel like the 5th gear really needs to be a bit longer.


I was pouring over the gear ratio/final drive chart I found and it looks like there are a few options:


2005/06 LGT 5MT

3.166 / 1.882 / 1.296 / 0.972 / 0.738 / 4.111FD


In 2007 (through 2009), Subaru must have been unhappy with the short 5th because they changed the final drive to 3.900.


You need to match the final drive ratio because the front diff is in the transmission, but the rear is not (unless you want to swap the rear diff, which means that this becomes a different project).


There aren't any Subarus that use the same 5th and final drive as the LGT.


You can find a few cars with a short 5th gear and the same final drive, but I think that's a mistake in the LGT. Your best bet might be something like the '98-'05 USM Impreza 2.5RS or the '96-'99 Legacy GT.


If you're willing to go through the work of swapping out rear diffs, driveshaft, and probably rear axle shafts (and a bunch of other stuff), you may as well do the 6 speed since none of the 5 speeds improve the car significantly to make it worth it.


I really kind of wanted a 6 speed. After doing some interesting research, I discovered that the STi 6 speed isn't a worthy swap though (unless you want the strength or the additional gear). Your final effective gear ratio is actually shorter than the stock 07-09 5th gear, and only slightly taller than the 05-06 5th gear. The only real worthy swap is the Spec B transmission.


So after this is all said and done. If you're looking for a compatible transmission for your LGT, there isn't a direct swap. You need to find the same transmission for your car.


If you're looking for a 6 speed that gives you about the same highway cruising as the stock box, look into an STi transmission. If you want a longer gearing, then you need to go Spec B (or JDM 04-07 Forester STi).

Link to comment
Share on other sites



Also check out Moore Performance blast plates. I enjoy them on every shift of my 5mt.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.


Engine Build - Click Here

Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Create New...

Important Information

Terms of Use