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RIP 2005 FXT 5MT
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950 Posts
Discussion Starter #1 (Edited)
I need a new transmission and I either want a STi 2007, 2007-2009 Legacy Spec B, or JDM SG Forester STi tranny swap. If I can find some used Spec B rear axles then I'll install a R180 rear diff. If I cannot source the axles I'll go the cheaper route, for now, and retain a 3.545 R160 rear diff.

I have seen a 2007 JDM Legacy Spec B swap for sale but I don't know if it has exactly the same specs as the '07-'09 US Legacy Spec B swap. My concerns are mainly about the gear spacing and the R180 rear differential type (same as US STi '07 internals/ratio?).

The goals for my Forester will eventually be high hp/tq power and top speed. Therefore, the upgraded diffs in the US STi 06-07 tranny swap might not be much of a factor.

Thanks in advance!

EDIT: I'll just stick with trying to locate a '07 STi or SG Forester STi tranny.
 

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2002 S
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2,702 Posts
The JDM Spec B trans will bolt up even though it had a 3.0, the bellhousings all mate up.
If you decide on the USDM Spec B six speed, just be warned that you have to change a few things for it to work(mainly the bellhousing) and it doesn't have a front LSD.
 

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2004 FXT
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72 Posts
Sorry to add to a month old thread, but the FSTI transmission has the EXACT same gear ratios as the usdm Legacy Spec B. The ratios for an 04 FSTI are 3.636 / 2.235 / 1.521 / 1.137 / 0.891 / 0.707, and the spec b is identical. So it would be much easier to find a spec b tranny or even bUy one new here.
 
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