So i recently just bought a subframe and I actually have no Idea if It has an LSD or not. I did contact the seller and asked him if he knew what year and model RX7 he took it from but he too, does not know. So are there anyways to tell if it's LSD or Open? Grass/concrete testing isn't really ideal because that means I have to take my current subframe out and sub it in and that's just too much work. Are there any OUTSIDE signs that it's LSD, or I also don't mind cracking it open to see what's inside, and If I do, What should I look for?

 

with both wheels off the ground, rotate tire on one side, the other should turn the same direction = LSD.

 

and this will work even when the whole subframe is not on a car?

 

there is a tag on the filler plug of the LSD Differential that says "fill with LSD oil only"
otherwise do what my friend above said..spin one wheel and the other should go the same way.

 

Does this work on Torsen? From what i have read about the Miatas, its not that simple on the Torsen diffs.