2005 WRX Rear LSD = 1998 Legacy GT?

[Huffer]

will a 2005 WRX rear diff bolt up to a 1998 Legacy? Any need for diff-specific axles, or will the stock Legacy axles work?

My google-fu is weak today.

[hallowpoint]

if the gear ratio is the same, it will work. i have a forester xt rear diff with lsd and it awesome!!

[grayguy]

It's not the right gearing. The newer WRX's have 3.54 rear ends.

[rougeben83]

http://spda-online.ca/modules/tinyconte ... tc_28.html (http://spda-online.ca/modules/tinycontent/rewrite/tc_28.html)

[impreza_GC8]

Incorrect gearing, you'd need the trans as well, amongst other parts. If you want an LSD you'll need to get one from a GC 2.5RS or something JDM. Bear in mind that the JDM mechanical LSDs need JDM axles which don't always conveniently come with the diff.

[Huffer]

What about swapping the ring gear from my car into the 05 WRX LSD? Wouldn't that bring the ratio back to 4.11?

the RS was an option, but it's kinda weaksauce.

EDIT. Nevermind, I took a look at the chart rougeben posted.

[rougeben83]

you can try an automatic WRX rear diff, those are FD 4.11 with vLSD.

You can always transfer the rear differential into your current R160 carrier, it's actually pretty common nowadays. They're all the same basically (even the carriers for the mechanical ones) KAG did a write up on how to transfer the lsd diff into an open diff carrier.

[KAG]

Yep, if it's an automatic (4eat) WRX, it'll already have the correct gear ratio for you to be able to just slide the entire diff right in there. But, if it's a 5mt WRX, you'll need to take the VLSD unit from the wrx carrier and swap it over to your stock diff.

Honestly, if it is a 5mt, you'd be better off just finding a 4.11 VLSD from any 00-01 2.5RS 5mt, 00-06 LGT 5mt or 02-05 WRX 4eat and plopping it right in there to save you some time and hassle.

[Okin DaVanh]

Yep, if it's an automatic (4eat) WRX, it'll already have the correct gear ratio for you to be able to just slide the entire diff right in there. .....
Honestly, if it is a 5mt, you'd be better off just finding a 4.11 VLSD from any 00-01 2.5RS 5mt, 00-06 LGT 5mt or 02-05 WRX 4eat and plopping it right in there to save you some time and hassle.


For the EJ22 owners out there: (I see 4EAT dropped so many times in this thread.)

Would this be possible??? or even Beneficial??

[mysubarusti4life]

I have a 98 Legacy GTY with a swap.. the LSD diff will fit, in fact, i used the same rear axles and stuff from the car, all you have to do is make sure the gear ratio for the transmission and diff are the same.. example, I am matched at 4.44 final drive