The Stovebolt Site Forums The Shop Area Driveline 47 3600 brakes

There are paper gaskets between the rear axle hubs and drums on 3100's as well. I believe their main function is to keep axle lube that may get past the seals from the inside of the drums and contaminating the brake shoes, making them grab. On the inside of the axle flange there's a "cup" that catches and routes leaking lube to a hole that matches up with one on the drum to so it goes to the outside of the drum. They do function to reduce rusting of the drums to the axle flanges also, but I don't believe that's their main purpose.