no 4x4

Forum: 

ok, had a nasty clunking noise, when on full lock with my 89 rocky!
so replaced the drivers side drive shaft and cv joint, oil seals etc etc.
so thought cool lets put some oil in the front diff and see if the 4x4 works!
well it really dont!

both hubs, locked in and you can turn the prop shaft?????? that shouldnt happen!
the transfer box locks in, as when in 4x4 it dont turn!
now i know both hubs lock in and out, as they have been apart cleaned and do work!
the problem is defo inside the front diff!
its coming to bits tonight, but does anyone have this problem or had it?
any pointers? i think the gears are stripped on some part of the diff? can i replace just bits, or should i try and get a second hand axle?