The Trailing Arm bushings and go bad at times as well. The Lateral Stabilizer Rod bushing and fail less often, but can be a possibility? What I do is start tapping around with a large rubbed mallet. Bushings, arms, springs and the exhaust system to try to isolate the noise.It is also possible the rear differential has some play in it. If you can turn the drive shaft a ¼-turn or more before the wheels start to turn, there is excessive play in the rear differential.