Rear Differential Mount Leak

[GDixon]

2008 RX 350 AWD

There is a round post-like appendage that comes out of the rear differential and mounts into what looks like a donut-shaped large rubber bushing. The bushing is located just a couple of inches forward of the spare tire.

My garage floor has what looks to be large oily charcoal colored drips under the rear differential at this rearmost point. In inspecting it either the bushing is fluid filled and is leaking or the post coming out of the differential is leaking since a black oily line is coming out of the contact point between the post and the rubber bushing. Does anyone know what this is, if it is a serious problem, and has anyone experienced it?

The nearest dealership is 60 miles away and I'd like to be prepared when going there with useful information. The dealership does not have a stellar reputation for service.

A search turned up nothing. Thanks.