door rattle

We just rebuilt these hardtop doors and they rattle pretty bad when going over bumps. Is there anything that can be done to reduce the rattle

This is not supposed to happen w/ my perfect car but, I've got a rattle coming from what appears to be my driver side door. It has 81k and I've owned it for 2 years. All it has needed so far is oil, so I'm somewhat chagrined that this has come up. I'm really not looking forward to the dealer...