I got some self adhesive foam type of sound-deadening stuff for the underside of the hood, and a heat/noise blanket ( which has a foil sandwiched between underlay) to put under the floor coverings..
I also just turn up the stereo to drown out the road noise. <img src="/forums/images/graemlins/kewl.gif" alt="" />

Im suprised that nobody has mentioned roof flashing, same and dynamat extreme, $15 for 12.5 sq. ft. at home improvement stores.

I'm sorry, can you clarify what material you're talking about?

He probably means soething like this stuff:
http://www.andek.com/H%20FLASHBBAND.htm

When somebody mentions roof flashing to me I think of thin sheet metal that is easily bent into whatever shape you need. I don't see how it could be of help except for filling in over an opening so you could put something like dynamat extreme over it.

As for the Flashtape, I could see where it could be useful. One of the goals of sound deadening material is to change the weight of the exterior sheet metal so it resonates at a much lower frequency. Anything that adds mass will do this. A few layers of flashtape could be a poor mans alternative. Another goal is to weaken the energy causing the metal to vibrate. To do this the sound deadener's use a material or combination of materials that absorbs the sound energy. Usually it does it by turning it into heat. Alternating sheets of lead and felt bonded together makes an excellent sound deadener and has been used in ships engine rooms for decades if not over a century. More modern methods substitute foam for the felt, and high density vinyl for the lead.

After reading the link Bogo posted on the sound deadener shootout, I'd be hesitant to use a roofing product. They aren't designed to withstand the sort of heat you can get inside a car.

When I replaced my heater core, I removed the entire interior(dash, supports, heater vents etc.) and lined the entire firewall w/ extreme dynamat. This cut down engine noise quite a bit.

I also did my doors w/ the stuff. After installation, the doors had a much more solid feel to them when you shut them and gave them less of tin can feeling. But unfortunately while on the trail my truck fell into a tree thus smashing in my door and I have since replaced it -- luckily it was the passenger door and I don't notice the excess noise as much.

Another thing I did that cut down on road noise considerably was herculine the interior of my cab.

But don't get me wrong, even after all of those things, it's still pretty damn loud going down the highway w/ 33" mud terrains. It just made it A LOT more tollerable.

All this talk about fancy sound and heat insulation products, I'm with Snowtoy, free to cheap carpet padding.

Carpet padding I installed 6 years ago solved my in cab heat problem on the FJ80 and the cab is much quieter.
And after submarining my 86 4Runner a few years back I also installed carpet padding in it with equally good results.

To each his own...just thought I would share
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