atb

I'm in the process of taking my interior rear quarter panels out to start installation of sound deadening material. I'm using dynamat.

One of my rear seats had come loose, so I went ahead and pulled the bottom and mid cushion portion out, and it appears that there already is some sound absorbant foam underneath the rear seat foam from the factory.

Here are my questions.

1) My plan was to lay dynamat down on the floor of the hatch aread including the spare tire well and over the rear wheel wells. Is this overkill or is this the way that the stuff should be applied.

2) Should I pull the foam under the rear seats out, apply the dynamat, and apply some of the dynamat sound absorbent foam in its place, or just leave the stock foam in place and don't mess with it.

3) When I go to apply the dynamat in the doors, should I apply any on the inside of the outer door skin, and in what configuration. Just l just lay a huge rectange in there, or is there more science to it than that. Do you entirely cover all of the other openings on the inner door skin?

4) Anyone have any pics of where they drilled the rear quarters to fill with spray on foam?

Thanks for any input or ideas.

j.kenzie@sbcglobal.net

1.): I think this is the right way to do the hatch area. (I used Brown Bread, but I think it's similar.) You can also add a closed-cell foam mat under the hatch carpet.
2.): No strong opinion but maybe dynamat foam is better that old OEM stuff.
3.): I covered the entire interior door panel, holes and all. If I need to access the window parts, I will cut the material and patch it back when I'm done. I understand that a 12" square applied to the inside of the actual doorskin will diminsh resonant vibrations.
4.): I removed my rear inner wheel well liners and shoved pieces of 2" closed cell acoustic foam up the rear pillars, packing it tightly. No moisture retention and removable. I also put 1/2" accoustic foam on the protected surface of all my wheel well liners, I have 7.
I was pleased with the overall results and did some measuring with a sound meter. I think you will notice a difference from your efforts too. I got most of my materials at a website called soundproofing.org
Good luck,

85fortheDrive

Thanks to a tip from Dave M above, I added mass loaded vinyl underneath the carpeting in the back hatch. While I've made no other efforts to diminish noise, methinks that Dave's #3 above is probably a huge reducer.

Let us know how she goes...

Tim

heinrich

Stock stuff is super heavy Adam, and it retains moisture. I'd pull it

Andrew Schauer

Adam-
I filled the cavities behind the rear speakers with expanding foam, and Dynamat'ed the wheel arch area in front of the rear seats. Made a noticeable improvement.
From what I have read about placing Dynamat/etc, the most efficient way to install it is in a "chevron pattern", with alternating strips of mat and bare areas. The chevron V-stripes would run diagonally to the panel you're installing on. Supposedly gives you nearly all the benefit of covering completely, but with about half the cost. Of course I found this out after I had already finished the project...

BC

The idea is to get the bare painted metal in the cabin at all corners and throughout. No Tar paper, no foam, no glue. This takes time, but will be the only way to get the full worth out of your work with the sound deadening material.