it might eb a LSD of some sort. i ahve absolutly no idea.
why do you lift the rear of ya jeep up.. and spin the wheel and and find out?
if you have QD.... it should lock up after 3-5 full revs. (cant remember which, was told by the service manager who claim thats how they check it from the maunel)
if its a LSD.. it will do that LSD thing...