I sold Dynamat starting back in the late 80's. I have no idea why I waited so long to do mine, it needs it badly. It's very noisy. In fact I got my Dynamat for free from my old boss as a wedding present (back in 2007) and I finally put it in last weekend. Wow, you really have to do this especially if you drive highway speeds often. Huge attenuation in noise. I did the front, rear doors. The spare tire well and rear side panels. It took 6 hours and besides a phillips and a 14MM socket you only need a clip tool and a small hook tool.
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