a good quick way to free up all the old gunge in your auto hubs it to take them off and put a dollope of engine opil in the bottom then run them for a while before servicing them properly!
If you take a decent close up of the internals and brake rings, we weill be able to tell you if they look ok :thumb2
Mine has fixed hubs, the slection process for 4wd is different and no need to reverse when changin back to 2wd, the instructions on the back of the sun visor should have the appropriate instructons for the hubs fitted.
I did have a brand new - still in sealed bags - set of springs for auto hubs, i offered them on here and had no takers, if i can find them (and it's a big if!) I will offer them again, free to anyone in need.