I know mine made the noise every time I was braking hard, so it was easy to replicate for service tech. If it's the carrier bearing it will most likely "sound off" when you're really hard on the brakes, causing the driveline to flex and misalign at the bearing. If this isn't the case I'm not sure what they'd be looking for. But I'd definitely have them start there as it sounds like the same issue. Good luck man, hope it gets solved.
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2014 GT MT TrackPack w Brembos, 3.73 gears
Came home with me 4/23/14
Ingot Silver with matte black wheels and emblems, SR Performance lowering springs, J&M adj panhard bar, BMR LCA's
by my 5 year old daughter and co-pilot