Could be a half shaft, or it could be some part rubbing on some other part due to worn front-end pieces. I've also had what I would describe as creaking from a shot wheel bearing. The worst was from a broken spring which was pointed out by a tire shop. I had to drive it 2 doors down to a regular mechanic and, apparently, instead of pulling the broken spring chunk out, they left it on and lowered the lift. The chunk creaked and squealed against something until I turned and then wedged against the brand new tires and started smoking like crazy. Good thing it was only 2 doors down!