What's the clunking noise??

Quick update, I added a bottle of the Motorcraft additive today and drove to work. So far the noise is very minimal compared to before. I haven't had time to do the figure 8s in the parking lot yet. Not sure what is in the little magic bottle that smells like T-Rex puke but it seems to do the trick. Thanks for the help everyone.
Fish oil. And yes it stinks to high heaven!