Jump to content
Ultimate Subaru Message Board

Adding a lsd to your older legacy.

Recommended Posts

Have you ever wanted to add a LSD to your older legacy. Maybe to help in the off road or just for some bragging rights.


Head over to your local newer salvage yard and ask a rear end out a 02+ WRX automatic wagon. Yes, you could find one from an older 2.5rs, but chances are it will have some higher miles on it a probably driven pretty hard. So why that combo you may ask. First all WRX automatics came with 4.11 gears (same as the legacys) and all came with a viscous limited slip standard. Second you need the axles from a wagon because they share the same width as the legacys, where as the sedan has a wider width. Now I’m not 100% sure you couldn’t use sedan axles, but I used wagon axles and they worked great.


The only prep you have to do to the WRX rear end is swap the input flange to the one that is from your legacy. That just takes an impact gun or a big breaker bar. Other then the flange the rear end is a strait forward swap.


The only odd thing I ran into was one axle was a little longer then the other by about a ½”. After mounting it I measured between the bearing in the hub to the rear end and the passenger side was just about a 1/2” longer. So the longer one went into the passenger side.


The main reason I went with this combo was the WRX wagons seem to be not as popular to get parts from as the sedans. I picked up my whole rear end with both axles with 8000 miles on it for $300. And I will never put the power to it that a WRX would so it should last me a good long time.


Keep in mind this will work with older legacys with 4.11 final gears or any subaru with 4.11 gears. I have heard in later years of the legacys they changed the final ratio to 3.90. So consult your manual or if it's old enough it should have the sticker on your rear differential cover what gear ratio you have.

  • Like 2

Share this post

Link to post
Share on other sites