Thanks, Erling! Having same Scraping/Rattling/noises complaint - recently acquired -lightly used- 2013 ACE 30.1. Threads indicate Schwintek motor/track rattling, or slide improperly installed. OTHER Solution posed is 1- some T-nut and bolt to replace the motor locking screw(found that); 2-and installing foam around motor; 3- and foam around long rod inside frame. All details visible on Lippert/Schwintek online pdfs. But NO info on how to make the fix. Any help from you, or owners who have 'had it fixed'. Unit is days out of warranty, so DIY is needed. Outside frame is riveted, with full body paint; so minimal invasion is desired. I read all related threads (and Cass Sumrall's saga), seem close to solution, but cannot tear into it unless I'm sure. Slide works OK, just noisy on the road / bumps, rough spots esp. annoying!
Edit: removed excessive quote.