I was looking at a 94 LC when I noticed that when you engage the front and rear lockers, the steering wheel was a lot harder to turn than the other ones that I have looked at. Steering works ok when you disengage the lockers. What's wrong? ???
That's normal. When you turn, the outer wheel travels further then the inner wheel and the differential allows this. When you lock the differential, the wheels are forced to rotate the same number of rotations even while turning, which mandates that one or both slip and dramatic steering forces are created. Obviously, this is not good to do on grippy pavement. Best to check them on gravel or dirt. Nothing wrong.