I have used it, the only problem I have seen is the edges want to peel off a vertical surface in the summer heat(closed up windows & out in the sun) if there is nothing else to hold it up. I used it under the OE type firewall pad, it has worked fine, but on the rear cab wall behind the tank the edges peeled back-but good heat-a/c type duct tape on the edges held it back on well. No one looks back there but me. Deadens sounds better than it insulates against heat, I got 3ftx100ft roll @a builders supply store for about $100,,Brian
