Yes, you take the hub-lock unit off with the wheel on the truck, just take the hub-cap off first. The unit is held in by a large round snap-ring that you can remove either with needle-noses or your fingers if your fingers are small enough. Then once the ring is out just work the hub lock around back and forth, up and down with your hands and pull on it until it comes out. DON'T hit it with anything! The O-ring should be replaced, it's cheap even at the dealership, I don't know the size of it, sorry. If it's really stuck bad like the previous poster just said, you're gonna have to tear it down and free it up that way, either way it's not that difficult. Usually a good soaking with PB-blaster does the trick though.