I used Silencing material on my Tundra and the difference was amazing. The problem is this stuff is heavy. I wonder how much mileage I would loose? Has anyone done this to a Prius? Does it need it? I have a ton if this material left over from the Tundra. http://www.gwfweb.com/tundra/pages/sound.htm
I don't think the prius needs it, mine is very quiet roll the windows up and on freeway can't even hear it( well a little maybe)
You'll be surprised once you add some to the doors. I don't have any but if I ever had spare money around, I'd get some dynamat and stuff the door panels. Whether the Prius needs it or not is a matter of perspective. Some said this is the quietest car they've owned and others said the noisiest. I'm in the middle. It's by no means the quietest (our Camry wins that) but by no means the noisiest (our old 97 Corolla beats that).
