I know this is an older thread brought back to life, but I noticed several people, after I posted, who eluded to sing the tape on the door pin if yo own a Newmar. I found a better way that is permanent. The door pin is designed to float so the door doesn't jam shut when the coach is not level.
Using a large wrench, you can unscrew the door pin and remove it. It has a large washer attached to the pin between the stud itself and the threads. I used a piece of flat plastic from a storage bin cover (white cover for those clear storage bins) and cut out a washer the same size as the metal washer on the door pin. I reinstalled the door pin with the new washer and tightened. Once tightened, the door pin was still capable of floating, but was tight. This insulator solved the door rattle.
Don & Mary
2019 Newmar Dutch Star 4018 (Freightliner)
2019 Ford Raptor