the drive axle nut is what holds the hole thing together, take your wheel off, and its that big center nut,(should be a 32mm nut in the center, most are 30-32mm) if its not torqued properly, or wiggled loose it could create a gap to where it clicks or clangs, most are torqued so good its prob not that but it could happen....

LOL, just noticed you said right rear?....rear wheel drive? or AWD?