couple of rear diff. questions

[patrickm1587]

Alright. I finally picked up a '95 j30 diff from a local junkyard today that has 140k miles on it. First question: how can I be 100% sure its an LSD? It doesn't have a sticker on it anymore. A guy told me one way to tell is if you spin the input shaft the output shafts should both turn the same way and they do. Is that right? Second question: do they make any upgraded bushings/mounts I can use? I don't want solid mounts or anything but I know they need to be replaced and I'd like to put something decent on there. And I read somewhere that I will need to get longer bolts to go in the front of the diff, is this correct?

[pella]

Just did this two weeks ago. i beleive all the J30 diffs are VLSD.i used all the same hardware that came off my 240 just put in the diff, and presto ten bolts later its in.

[terry_240sx]

how can I be 100% sure its an LSD?

try spinning one output shaft, they should both spin the same way.
you can also try hand turning both of them opposite directions, which should be tough to do but possible.

do they make any upgraded bushings/mounts I can use?

I decided to just stick with the stock ones, and i think they're just fine.

And I read somewhere that I will need to get longer bolts to go in the front of the diff, is this correct?

You don't need longer bolts if i remember right, but if you don't get the bushings you'll need a huge washer to compensate for the bigger hole.
hope this helps