Update. I tried to get in to the only rv service shop locally, but they were backed up. The manager gave me the name/number of a guy who might be able to help. I called and talked with him. He asked the brand and type of AC and when I told him, he said iWork on those all the time and have most any part you need! He works on high end tour buses, RVs and other stuff that use the Dometic Low profile Pinguin AC. Anyway, I took to AS to his shop, he got on it right away. Found the fan motor shaft had very excessive play and was likely causing noise. He showed me the motor I had and a newer one they were replacing them with due to reliability and quoted me a price to replace. I was ready to do it, but he suggested a simple, maybe temporary fix to keep movement down and letís do this first and see if your problem goes away. If not, then we can look at replacing motor assy or something else. Well, the simple fix seems to be keeping rattle to almost unnoticeable. Happy camper.
The Colonel and Southern Belle