4x4 front axles

[dadsgreentruck]

So I've been hearing a growl/howl that seems to be coming from the front end of my '96 4x4 and is slowly getting worse. I've assumed that at 150K+ miles, its one or both front hubs starting to go.

I was doing the front brake pads and rotors this weekend and noticed that (with the truck in 2WD) as I turn the passenger side front hub, there is a fair amount of drag and the axle shaft turns with it. Is this supposed to happen? I always thought the hubs would freewheel until told to lock.

--Tim