I was driving today and noticed a chirping noise, much like when your serpentine belt or idler pulley are bad. However, it wasn't worsened with engine load so I was kinda confused.

Popped the hood, got out and, to my surprise, it wasn't coming from the engine bay. It was coming from the rear end of the car. Got on the ground and took a look...couldn't really do much considering the car was still hot and running. The noise seems like it's coming from the area around the differential.

Any ideas? There's no noise when the car is off, and the noise isn't worse when driving. It's just kinda there when the car is turned on. Nothing about the car feels different either. Appreciate any help in advance.

Edit: It's probably worth mentioning that my rear diff bushing went bad, so that could be part of the problem.

 

Rear diff bushing or possible exhaust leak, air pushing through small cracks or gaps causing the noise.