I recently left the back window partially down on my 1991 Blazer during a heavy rain strom. I was away from the truck for a couple of days and when I returned I opened the door and was overcome with incredible stench (first thought was a dead animal in the truck). I recently finished some interior work last month so the truck was pretty clean, it was clear nothing dead was present. I traced the smell to the back, the saturated carpet near the tailgate. I pulled the carpet back and saw that it was soaked right through to the metal floor. My plan was to cut out the soaked insulation like pading and replace it with similare from Home Depot. Between the carpet and the padding was a hard black covering of some sort, when I pulled it back, it broke into small pieces, breaking off inside the black pastic covering. What is this piece? I am thinking it is something to reduce road noise? I'm not sure if this piece was contrbuting to the odor, it looks like it is pretty much sealed in the plastic covering, therfore water wouldn't get in? What happen if I take it out?, will I get a ton of road noise with just soft padding and carpet? By the looks of it, I believe it to be something that was put in at the factory?