suspension problem

Okay, this morning on my way to work I did a couple nice peel outs. After the second one, I slowed down and turned into the neighborhood my work is in. Then I started to hear a random rattling noise from the rear end. Sounds like metal on metal rattle with acceleration at low speeds. What is...

So i have the usual suspension pop in the steering rack that everyone develops at one point. The usual fix for this is to replace the steering rack bushings, which I have with polyurethane this weekend. I also had them align it while the car was in the shop. I still get a pop in the right side...