Just serviced the pilot brakes for the first time. Noticed that the inner pad wore faster that outer on passenger's side. Tried to take out sliding pins. One came out easily. The one with a rubber ring at the tip took quite some force. It would appear that the rubber ring has swollen for some reason and it seals the sliding pin hole with force. Not sure why it did that since the lubrican is the original from factory (This is my first brake service). I could file down the rubber, to make it fit more loose, or I could take if off permanently. Does anyone know what is its purpose?