Rear End Rattle

[bem36858]

I have a 2003 GMC Sierra Z71 and my rear end started making loud rattling noise when I hit bumps, it rattles in rhythm with the drive-shaft but I don't feel anything in the steering wheel so i don't think it is an issue with the drive-shaft itself (hopefully). I have checked all of the basic muffler mounts and panels and nothing seems to be loose. I have narrowed it down slightly... when it makes the noise I depressed on the emergency parking break slightly and it stopped instantly. So I pulled apart the rear end with my Pa and fixed a gasket that was leaking break fluid on the hub. This stopped the noise only for a while (about 5 days or so) then it came back. My dad said that it could possibly be the parking break needing an adjustment and it could be rattling against the hub. We plan to try and make those adjustments this weekend, but other than this the problem has left us bewildered for about a month. I've had insight from multiple mechanics with no results. Let me know if you have any other suggestions.

 

Beau