Originally Posted by elp_jc
Bolts #2 and #3 are identical, and all they do is support the exhaust pipe brackets (left and right) to the differential, so don't worry; it's nothing serious. The orange hangers attach to those brackets and the exhaust pipes. The bracket was just making a racket against the differential (or pipe possibly touching driveshaft), but it's definitely not the differential itself. It's weird that the bolt just broke when there's little stress on it. Glad it wasn't a more important bolt.
The two front bolts that go through the exhaust hangers also go through the rubber isolated mounts on the crossmember.
There are only three bolts holding the differential on, two smaller diameter in the front and one larger one on the rear. I am under the car right now looking at it