There is a popping noise that coming from the front right tire area of my 2004 GMC Yukon when I back up and turn the steering wheel to the right. The front differential bearings were replaced recently b/c of the same noise and leaking differential fluid. I have had my car back for a total of 3 days. The mechanic told us that he would replace the bearings and to bring it back if the noise comes back to replace the whole differential. I am wondering if you think it is the differential or something else.