Heard back from the dealer earlier this afternoon. First thing he said after checking out the car (test driving it) with his technician was "It's normal noise" !!!! HA just as I suspected I thought. I talked to him, telling him I was recommended to the dealership by someone from the xfire forum which is a global community and explained to him I was fully aware of the rear differential problem in the '04 models. Once he realized I was obviously informed and well prepared he put me on hold and came back telling me to fax over my temp. registration (bought it used two weeks ago) and said his boss would take it out first thing tomorrow morning and he said "we will make this happen for you".

Now I know nothings been done yet to the car and I am crossing my fingers hoping everything will pan out and they will make the repair. I even sympathized with him understanding its an expensive and labor intensive job (replacing the rear differential) but explained to him it was under warranty and I wanted it done.

He originally explained to me it was "normal noise" and "nothing to worry about". However I made him admit it was the differential and after explaining to him the humming sound was only going to get worse (which I am sure he already knew) he changed his tune.

Case in point if it wasn't for this forum I would have had no idea what was wrong with my car, gone into the dealer empty handed and clueless and had the wool pulled completely over my eyes as my car continued to get worse!

I will let you know how the repair goes (i.e. time taken, costs (under warranty), and helpfulness).

Thanks!