Tracking Arm The Cause

[cwgreen1971]

My truck recently started making noise when hitting decent size bumps, I shook the bed from side to side and it sounds like it is loose. It doesn't make the noise up and down though. I had a friend check out under it while I shook it, he held on to the tracking arm and the noise disappeared. Would this cause all of that noise? I have some new bushing from another truck I am putting on this weekend, the old ones are pretty much gone.