Attention: TDR Forum Junkies Wanted to post this for everyone that would love to have there truck as quiet as a lexus with out having to spend $3000 big ones to have someone at a stereo shop do it half ***. I found this stuff called Jiffy Seal at Lowes Hardware for $16. 00 per 50' x 6" role that is used for sealing the edge of windows in construction. It is made of a tar compound that has adhesive on both sides. I compared it to a popular sound deadening material called HushMatt. It was very close in thickness and was just as sticky. The difference was that the Hushmatt has one side that was foil painted black and cost about 300 times as much. I had my wife while on a weekly market trip pick me up the heaviest duty role of tin foil she could find. After pealing the first piece and adhering it to the tin foil and trimming a bit I found that I had made the same exact stuff as the HushMatt for the most part. A Hell of a lot cheaper. Oo.
I started with the inside of the doors and worked my way to sealing all the interior surfaces of the doors and the holes that they leave open from the factory. There is a source of a bunch if noise right there. If you tap on the exterior of the door before the matt is put on it sounds like a drum. The difference is astounding.
I took it for a test drive and found that the doors sounded great but I could hear a source of more noise in the back seat. After taking all the back seats and hardware out I saw what equated to a large drum back there. I covered the entire rear cab facing the bed and then pulled out the floor matting under the seats to find the same issue. The carpet is pretty good at killing the sound due to its foal underlayment but this stuff was 1/8" thick of nothing.
One really bad source of noise was the cabin pressure vents behind the rear seats. I did seal those up but I am not reconsidering opening one of them up due to the high cabin pressure when the A/C is on even the low setting. On high I felt like I was in an airline with pressurization problems. Figure I could always get in the truck if a have a diving accident and need a pressure vessel 
.
The difference is night and day :--) If your looking for a way to make your truck nice on long trips, This is the way. I will post before and after tests with a sound pressure level meter here soon. I will go for a test drive at the dealer with a stock unit on the same street, speed, and lane as I test mine. I can’t wait to see... or should I say hear the difference.
Enjoy,
Adam
Check out the insulation installation in my rig pictures here:
https://www.turbodieselregister.com/user_gallery/displayalbum.php?&albumid=17479
I started with the inside of the doors and worked my way to sealing all the interior surfaces of the doors and the holes that they leave open from the factory. There is a source of a bunch if noise right there. If you tap on the exterior of the door before the matt is put on it sounds like a drum. The difference is astounding.
I took it for a test drive and found that the doors sounded great but I could hear a source of more noise in the back seat. After taking all the back seats and hardware out I saw what equated to a large drum back there. I covered the entire rear cab facing the bed and then pulled out the floor matting under the seats to find the same issue. The carpet is pretty good at killing the sound due to its foal underlayment but this stuff was 1/8" thick of nothing.
One really bad source of noise was the cabin pressure vents behind the rear seats. I did seal those up but I am not reconsidering opening one of them up due to the high cabin pressure when the A/C is on even the low setting. On high I felt like I was in an airline with pressurization problems.
Figure I could always get in the truck if a have a diving accident and need a pressure vessel . The difference is night and day :--) If your looking for a way to make your truck nice on long trips, This is the way. I will post before and after tests with a sound pressure level meter here soon. I will go for a test drive at the dealer with a stock unit on the same street, speed, and lane as I test mine. I can’t wait to see... or should I say hear the difference.
Enjoy,
Adam
Check out the insulation installation in my rig pictures here:
https://www.turbodieselregister.com/user_gallery/displayalbum.php?&albumid=17479
I like it cause I get stuff done that I "need" to do! 
