In January of 2018 I had front brakes and rotors replaced on my 2002 Sienna. At that time I also have the caliper pins regressed with the proper silicone grease. Left side was very messed with extremely uneven wear on the pads due to dry caliper pins. About a month ago the right wheel started developing a subtle scraping sound when I apply the brakes. I meant to do it anyway but since it's been over two years I thought it time to regrease those caliper pins. I'm easy on my brakes so both sides had about >50% pad left. On the right side, since that's where the sound was coming from, they paid a little more attention to the condition of the rotor and the pads and so on and so forth and everything appeared fine. So the pins and ears and shims were regreased and everything put back together. The only thing is, the mechanic pulled out the lower pin too far and that is the one that has a little rubber grommet on the end. It hadvswollen and he couldn't get the pin back inbecause of it. He seemed to feel that was not needed and so just flicked it off and put the pin back in. For the life of me I don't know why I didn't question that at the time, because I'm pretty sure car manufacturers don't put on extra parts that you don't really need...especially in brake assemblies. Plus, I never knew anything about those grommets before, or that they can swell. If I had I would have bought new ones to replace them out of hand while the brake guy was in there. So, there's the history. Everything was put back together I got down the road and everything seemed fine for a couple of days and then the soft scraping sound started again. So two questions. 1. At this point, what could be causing that low scraping sound? 2. Anyone have a firm idea of what of what the grommet is fir on the lower pins of my front disc brakes? And what bad can happen if it's not there?