Rear wheel noise that comes and goes

What is your question?

There is a light thumping noise coming from the rear. It is not constant. Sometimes it is noticeable at high speeds but goes away when I stop or sometimes after hitting a bump. It is not a loose tire, nor a bad tire.

What makes this problem better or worse?

Better after a complete stop

How long has your 2005 Chevrolet Avalanche 1500 had this problem?

Month