Do you have mystery dirt in-cab? It's probably coming from this thing!
If you have unexplained dirt and dust showing up in your rig when you KNOW there shouldn't be, pull your shifter console off and take a look where the shifter linkage goes through the floorboard (the small creased spot on the passenger side of the boot in above pic). This spot sees A LOT of cyclic motion and will inevitably fail at some point. We don't like dust, and this has been one of the best fixes so far!