I heard a squeaking noise coming from behind my car while I was driving it today and I heard a lot of pinging at the rear of the car after I turned it off. I suspect that the pinging is probably just the exhaust cooling down, but I inspected this squeaking noise a bit further and so I put the car in neutral and pushed it a little, I heard a continuous loud squeak as long as I pushed the car and had the tires moving. I s this the differential?