Insulation (somewhat off-topic)

[The Warden]

Hello! This is a bit off-topic; I apologize for that, but I think I can get the best answer here. I know that there are those on here who have made efforts at insulating their cars from noise and heat/coldin various spots. What exactly did you use? Is there one method of insulation that'll keep the outside temp from getting in and that will keep noise to a minimum?

I'm looking for something that I can use all around (floor if I ever decide to take the old stuff out, replace the hood pad, roof above the headliner, area under the rear seat cushion, etc) on both my car and my truck. I'm asking at the moment because I needed to pull the headliner in my truck for other reasons (namely: it's falling down ) and would like to get the roof insulated, and so far, it doesn't look like anyone on the "other" site has any ideas (so far, the only idea that's been mentioned is to inject foam, but I don't really like that)...I think that having the 300D's making me soft.

The idea is to do this piece by piece; if a piece of interior trim's removed for other reasons, I'll hit that spot (i.e. if I use Thomaspin's procedure to completely lube the sunroof, I might hit the sunroof piece behind the headliner with insulation while it's apart), although I probably won't tear stuff apart solely to insulate stuff...unless I get bored one day.

Thoughts and comments appreciated. Thanks in advance!

[sixto]

There are various products offered in the DynaMat line used primarily in stereo installation. They have a heavy duty liner that their tech support folks tell me will work to augment the belly pans in an SDL. ATF can collect in a belly pan and they say that shouldn't be a problem. Finding the right adhesive migt be a problem. The stuff's not cheap or light, though.

Sixto
95 S420
91 300SE
87 300SDL
83 300SD

[jbaj007]

Sound insulation has three primary methods.

1) absorbtion
2) barrier
3)dampening

Some ways to use materials towards these ends is discussed at McMaster-Carr. Put in the "find" box at this site (sorry, it won't direct link) and a page of explanation with suggested materials should appear.

McMaster-Carr: http://www.mcmaster.com/

[coachgeo]

some product links I searched out a few weeks ago on this subject

http://www.scosche.com/accumat/

http://www.soundcoat.com/Pages/solutions.html

[BoostnBenz]

With all the people doing this insulation now, finally got me thinking maybe I should too. I think for the interior I'm going to be cheap and use some carpet padding, relatively thick stuff for the floors and light stuff for the door panels. My uncle lays quite a bit of carpet, so I can probably get it all for free. However I almost think I'll have to get something special for the firewall as I don't want to test the heat properties of the padding.

Why take the old stuff off of the floor? With carpet padding it not only serves as a sound deadener it'll also make your carpet softer feeling and is much lighter than dynamat.

[jerryb]

I have used quite a bit of dyno-mat type stuff on my dodge diesel, 24 sq. ft. I also sprayed the underside of the floor with a liquid sound deadner that was like an undercoat. I used both dyno-mat and a 3/4" foam sound deadner on the back panel. I put double pad under the carpet. I spent about $300 in material and a day and 1/2 and you would need a very sensitive decibel meter to notice the diference. I spent $180. on sale for new speakers, that was money well spent, it now seems like I can play the radio at a lower level but not hear the engine. My 300SD is much quieter than the dodge, but if it wasn't I don't think there is much tha could be done except for pluging holes etc.

[psfred]

In the truck, what you want is asphalt sound deadening material on the floor and firewall, fiberglass (same stuff as the MB) on the exterior firewall, and heavy foam padding (carpet padding, the really dense expensive stuff) inder the carpet, and in the roof. All this will help reduce the noise, but since the cab is bolted to four rubber mounts, you are still going to get all the noise transmitted by direct vibration, not much you can do about it.

Doors are going to be more diffucult, since you cannot simply stuff some padding under the liner. Some more sheet asphalt sound deadening (I assume DynoMatt is the same thing) on the inside of the outer panel will help -- you don't need to completely cover it, a chunk covering about half the surface in the center will help almost as much as the whole surface -- and make sure you have a good heavy plastic liner in place.

More sound deadening behind the seat will reduce the "booming" of that panel, and gluing on some more dense foam won't hurt.

Heat mostly comes in the windows, so you can't do much there except make sure all the seals and window channels are in good shape.

A truck cab isn't rigid enough to keep the sound out very well, unfortunately.

The MB is much quieter because MB makes quite, relatively vibration free engines, mounts them on vibration abosorbing, mounts, then installes them in a rigid passenger compartment with very few large, flat panels. They liberally apply sound deadening materials, and spend quite a bit of time and money makeing sure vibrations don't get transmitted to the body to make noise. Ford just slaps any old stuff together and rolls it out the door -- since everyone tramples the crowd to buy them, obviously this is what they want....

Peter

I got some stuff called Q-Pads from my local Auto Quest store. These are adhesive backed 1-foot squares which you adhere to the metal. They are not cheap, around $6.00 each I figured out, but I think they work very well. They are quite soft and you can tuck them into recesses, ridges, and valleys quite well. Supposedly they provide moisture barrier as well. I used them on the floors of my 300td after carefully sealing around the new metal, and really felt they were easy to work with.
My bro-in-law tells me that they are used to deaden the sound of a subwoofer so that it's tighter and doesn't rattle the car...