Hi guys,

I'm tracking down a leak in the right bottom corner of the rear windshield and could use a little help! The seal looks to be in good condition (pliable and no cracks), so I started poking around and found some pieces of gray "something," under the seal in the area that is leaking. The stuff in there is dark gray and kind of feels like clay, though it did not melt when left in water overnight. I went around the rest of the seal and didn't see any of this stuff anywhere else under there, so I think the previous owner bought something to try to stop the leak, but that stuff has deteriorated.

Does anyone happen to know what this stuff could be? Also, is there something that I could put under the seal to stop this slow leak? Thanks!