So, for some reason, I thought it would be a good idea to try to soundproof my diesel Benz this past week. At first, I thought that I would start fixing some things that were starting to bother me. I started at a junk yard by picking up some parts to fix that air leak in my fuel system. I then found some very nice interior pieces and dome lights. It was a real nice Saturday.

It's now midnight 2 weeks later after my small quest to fixing things has surmounted into a very large project including a new stereo (my old one was broke), new speakers (might as well), and a project that I've had interesting in for a while, soundproofing my entire car. Don't ask me how the train of thought went. I'm still trying to remember it. I want to caveat here that I am not trying to break any sound system records or destroy the neighbor's windows. I actually don't listen to very loud music, in fact I am usually caught listening to political talk radio. The reason that I am doing this is to try to eliminate as much road and engine noise as possible for a more comfortable ride.

After hours and hours of research, I decided that the best way to soundproof my car would be to use the 3 layer approach as described at sounddeadenershowdown dot com. The first step includes laying Dynamat as a sound-deadener, adding a layer of closed cell foam to block some noise, but mostly to decouple vibration from the third layer which is mass loaded vinyl and used to block noise. Yeah, it's gonna be a pain. I haven't even gotten to this part, and I'm already not looking forward to it. So, there you have the 3 layered approach. I will deaden resonating panels and block noise using MLV. The foam is in there somewhere too.

In my now obsessive quest to soundproof my car (as close as possible, at least), I've spent hours tearing out the entire interior, during which I decided that I'd need to get new carpet. I've also started a very long list of materials and projects that I will need to complete or buy. Am I insane?

Here's the plan:

I bought 100 sq foot of Fatmat vibration dampener, 200 sq foot of mass loaded vinyl (bought 150, they gave me 200, I later realized) and I am ordering 8 yards of Raamaudio's Ensolite foam. I have the interior taken out (see photos) and am working currently on taking the stock vibration dampener mat out. After this is out, I will cover most of the bare metal, but I won't be excessive. One layer should be enough to dampen the panels. I will then lay down the Ensolite layer with contact cement to cover everything. The next layer will be the mass loaded vinyl. This will be laid using contact cement again over the Ensolite. In problem areas, I will double up on the MLV.

I've searched fairly exhaustively on this forum for a documented project similar to mine, and I've yet to find one. For this reason, I've decided to use this to document my project so that it will hopefully be useful for someone else down the road.

Tips:

There are at least 5 different stock sound deadening materials in the 300td. Some of them seem to be pretty decent. Some come off easily with a little heat, and others refuse to come off without scraping every inch with a screw driver. Underneath the driver and passenger mats has been the worst, second will have to be under the console. Everything else has been pretty easy.

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