[BR3W CITY]

Deadening is great, but I'll toss in my .02

While I agree with covering the whole floor for vibration/sound/heat resistance...thats really the only thing that benefits from complete coverage. I've seen people waste a TON of cash and add a TON of weight by trying to dynamat everything, for pretty much no reason.

On a door panel, 1 or 2 10x10ish squares will add the mass to the door, and help cancel out vibrations from the door or the speakers. Same goes for people who do the whole roof lining, or the whole inside of the firewall.

Dynamat is 1 single tool in the list of things to use when prepping your cab. Peel n stick works great for the price, and due to its thin-ness, you can bend it easily into tight areas. It also works great for floors because unlike dynamat, it doesn't add 1/4 of depth. Nothing sucks more than finding out your carpet looks like a poo-diaper because of all the d-mat under it.

Spray lining like lizard skin offers similar benefits, and more in the way of heat resistance. Its better for complete coverage, and can get into contours the other stuff cant. Using it on the underside of the cab floor will not only help rustprotect your undercarriage, but offer the same benefit as dynamat.

On the firewall, there are thermal barriers that offer better protection over a thin layer of mat, vs building up layers of the stuff.

While SPL/DB cars may be a slightly different story, even they use a variety of materials to deaden the car. A single mat kit can do most of a truck, if you use it correctly.