In my experience, bad carrier bearings usually just cause a vibration and don't actually make any noise when they go bad.

But the noise while decelerating definitely sounds like the rear-end/differential to me. Check to see if it's leaking at all...that should give you a clue.

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Current cars:
2000 ML55 AMG, 174k miles
2003 C240 T-Modell, 202k miles
1995 S320, 207k Miles