One of my goals for this truck is to make it at least as quiet as my second generation cummins dodges were. My first step in accomplishing this task is spraying sound deadener on the outside of the floor. I thought this would be easier if I stood the cab on end.As I,ve said before, this cab pretty is rust free. You can see the factory 4-speed hole in the tunnel as well as the round hole I put in for the NV4500 shifter. The round hole was barely big enough so In the process of patching the other hole I enlarged the new one to factory size.
Here you can see the rough opening of the new hole and the patch on the old. You can also see two smaller holes. These are the end radii for the transfer case shifter.
This shot is from the inside. The black on the floor is POR 15. I put it on all the surfaces that showed a hint of surface rust.
Back on the bottom side, I went over the floor with a cup brush in an angle grinder and followed that with a scotchbrite pad. Then, I used brushable seam sealer on all the seams and on my patch. You can also see the finished transfer case shifter hole.
Here is the ugly mess of sealer and patch.
Next, I started spraying the sound deadener with an undercoating gun. You can see the texture of the first pass.
The plan is to get about 1 mm thickness per pass and do two passes. The temp in the shop is below 50 and I have to put my halogen lights on it to get this water based stuff to dry.
About halfway through the first coat.
This is the product I am using and the gun. The stuff is called Spectrum and its made by Second Skin. It runs about $60 a gallon, and it is thick stuff. It goes on a bluish grey, but dries black. It seems pretty hard when It dries. I have right at a gallon on the underside of the floor with two coats.
The finished product.
After setting the cab back down on the floor, I also did the engine side of the firewall with two, or was it three, coats. That was a week or so ago. Today I scuffed and cleaned the inside of the cab and shot the first coat on the inside of the firewall, the floor and the back wall.
I have right at two gallons on the cab as of now. The second coat on the inside will take most of a third gallon.
The texture is not bad and I am thinking of using it on some exposed surfaces and painting over the top of it. I did put it on my kick panels. They may get covered with plastic trim, but then they may not.