Outback XT or Legacy GT transmissions

[Rasmus]

Rather than use the 2006 WRX transmission that came with my donors parts I swapped it for an Outback XT trans. For my application, the gearing was better.

2006 WRX gearing:

1st 2nd 3rd 4th 5th Final
3.454 1.947 1.366 0.972 0.738 3.700
Legacy GT 2005-2006 (TY757VBAAB):

1st 2nd 3rd 4th 5th Final
3.166 1.882 1.296 0.972 0.738 4.111
Outback XT 2005-2009 (TY757VWAAB):

1st 2nd 3rd 4th 5th Final
3.166 1.882 1.296 0.972 0.738 4.444

Main problem is that the OTX and LGT trans don't come with a Speedo Gear or Speedo Sensor installed. The port for the Speedo Sensor and the boss that the Speedo Gear Assembly runs in are all cast into the case. The parts are just missing.

Based on two threads off of Nabisco Thread 1 (http://forums.nasioc.com/forums/showthread.php?p=22564870#post22564870) Thread 2 (http://forums.nasioc.com/forums/showthread.php?t=1992585), it looks relatively straight forward to purchase the parts from Subaru and install them myself. Plus I already need to crack open my case to install a limited slip.

Parts with Part Numbers needed:
Shaft = 32713AA002
washer = 803012060
upper snap ring = 8050121020
lower snap ring = 031512000
Gear = 32714AA190 (might need a different gear for the LGT trans)
Seal = 806712100
Speedo Sensor = 85082AE000

[C.Plavan]

If you dont need the MPH (I have a data logger dash with gps speed)- Get a VSS simulator like I did on my Legacy GT trans. http://www.enginewiring.com/catalog.htm

Worth noting: Both the Legacy Gt and XT have beefier gears over the normal WRX trans.

[FlatironsTuning]

The Legacy and Outback XT have the same gears as the 2008 - 2014 WRX.

We did a comparison of them with pictures a few years ago. Here is the link:

http://flatironsrally.typepad.com/faq/2010/05/comparison-of-subaru-gear-sets-wrx-legacy-gt-sti-ra-and-more.html

The other key difference is the final drive, which is something else to consider.

[Rasmus]

I hadn't even considered gear thickness when I selected my transmission. Just gear ratio's and final drive. Guess I got lucky and ended up with thicker gears.

[Sgt.Gator]

Small correction on the LGT years:
3.166 / 1.882 / 1.296 / 0.972 / 0.738 / 4.111FD - '05-'06 USDM Legacy 2.5GT
3.166 / 1.882 / 1.296 / 0.972 / 0.738 / 3.900FD - '07-'09 USDM Legacy 2.5GT

If you are road racing the 4.44 will limit your top speed pretty badly. For street and drag racing it will be great.

I bought a JDM Forester STI 6 speed and swapped it into my LGT race car a week ago. The LGT 5 speed will go in the 818R.

All the data is in the The Transmission Thread Sticky. But here's the link to the speed gearing calculator: http://www.teammfactory.com/gearcalculator.php

[Rasmus]

Thanks for the LGT correction.



If you are road racing the 4.44 will limit your top speed pretty badly.

I don't know.
http://i.imgur.com/5CfOOxl.png
If I limit myself to 8800 RPM and 24.5" tall tires I can get up to 148 mph in 4th and 195 mph in 5th. I don't think I'll have enough horsepower to push 195 mph of air out of the way.

http://i.imgur.com/eNOQao8.png
If I limit myself to a more reasonable 8300 RPM and larger 25.0" tall tires (255/40-17 or 255/35-18) I can get up to 143 mph in 4th and 188 mph in 5th. I probably still won't have enough hp to push 188 mph of air out of the way.

[Jaime]

BTW, I swapped the 4.444 ring and pinion out of mine and put in a 3.9 set. Is anyone in the market for shorter gearing?

[Sgt.Gator]

Those rpms will get you there. I limit my rpm to a much lower max, 6800. With my turbo that's as far as it can go anyway.

[C.Plavan]

Thats why I got the 4.111.