I have a 97' Expy 4x4. I am getting a bumping noise coming from the rear when i go over small or large bumps at any speed. I was told it could be the rear swaybar bushings? Is this true?

 

I've got an "98 doing the same thing.

 

Unless you can pin point it directly, I would start with the cheaper/smaller possibilities. I plan on keeping my 99 for a while and Im running into several small maintenance issues. So it wont hurt to replace those things anyway

 

I replaced all appropriate bumpers on my 98 several years ago with Poly-Urethane Inserts. Replacing all of the inserts front and back. They stopped the problem you described, and made the ride substantially firm. I have 20" all weather tires, and the ride is well worth the effort.

You can rebuild the arm with poly inserts. If that was the only problem. Also watch out for substantial rust on the rear control arms.