2004 Chevy Silverado Clicking

I have a 2004 Chevy Silverado and there is a clicking noise coming from under the vehicle when the truck is moving slow (~10mph). The clicking noise goes away at speeds faster than 10mph. I had the rear universal joint replaced and all other universal joints inspected. The clicking noise does not get worse when the wheels are turned and there is no indication that the cv joints are going bad. The truck does not vibrate at high speeds either. Is there anything else that could be checked out? The transmission seems to be operating as it should. I am really baffled by this slight clicking noise. Any ideas or suggestions would be great. Thank you.