Border411

All of a sudden I am having this issue I cant fix. When I roll down the windows only part of the way, then roll it back up, there is an oily line horizontal to the weather striping on the inside. This is ONLY happening to the front windows though! I rolled them both down then took a microfiber towel with some Stoners Invisible Glass and wiped down the inside of the weatherstriping when I first saw it, and a whole lot of black oily looking crap came off...but it kept coming and coming and....well you get the point. Where is it coming from? Anyone else having this issue?

By the way...I didnt use any protectant or anything on the doors which may have leaked, so it isnt that.

Shaun