Today when I was turning in a parking lot I heard my tiers chirp. It made the sound whether I was accelerating, braking or coasting. It only did it when I was turning to the left. I repeated the turn several times to figure out where it was coming from but I couldn't tell for sure. I think it was coming from one of the back tires but it seemed to switch from side to side. I got out of the car to check under all four wheels but nothing seemed amiss. When I turned to the right, I hear a clunk and then everything was fine. The chirping went away and the car was behaving normal again. It never came back.
I suspect this had something to do with the differential. Maybe it was staying locked when it should have let go. I’ve never changed oil in the differential and I suspect the previous owner hasn’t either. Would that fix it? Has anybody else had this problem?
Thank you all for your help.

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