Sound Proofing

[Vegas Teacher]

Hello All:

I am still in the marathon of getting my truck ready, on a teachers salary I do a little bit at a time. Anyway Jack is trying to convince me to tackle doing the sound proofing on my own. I know how to turn a wrench and how to take things apart. However those of you who have done this before can you tell me about some of the pitfalls I might run into. Something as simple as changing the cab airbag was derailed by a rusted nut and bolt that would not let go, so it cost me a tank of gas, drive to Pahrump, getting yelled at by Dolly Trolley and having to buy him and Vegas Flyer lunch.

So if I do this I want to do it right. I am looking to tear the inside of my cab down to the metal. How hard are the doors to take apart. How much can I remove even on the dash. How hard is it to remove the closet and storage. 

Can I insulate between the firewall and the cab to reduce even more noise? What kinds of sound insulating material can I use there. 

I plan on taking it over to Dennis Kansas this summer for Jack to put a bed on for me. Jack Mayer is a really great person and his given me excellent advice. He even took the time last summer to talk to me and gave my wife and my parents a tour of his facility.

Looking for advice and or pictures you can share with me.

Sincerely,

Cory Ossana - Vegas Teacher

[Moresmoke]

Haven’t played with the doors or under the dash much so can’t help there. The cab/sleeper walls are mostly held together with double sided tape, and a few upholstery anchors. The seatbelt bolts will teach you a few new cuss words, but should come out.

The inside of the sleeper walls is pretty well stuffed with polyfil insulation. Not sure how much you will gain by changing it out.

[Alie&Jim's Carrilite]

Cory, 

Its not hard, but you have to have some patience and determination.  There are you tube videos to guide you on the door part. 

The interior closet are usually tight.  A 3/8 impact helps since the bolts are in tight quarters.  If you unbolt the seats, door threshold plates, you can roll the floor material back a good ways.  I'd put the material as far up the firewall as I could.  Fabmat and Sounddown are the brand names I know.  There are generic materials available well.  A lot of the truckers put 2 layers in. In the door panels, you don't have to cover the entire door skin, covering what you can reach deadens the sound enough.

 

[jenandjon]

I put this R-tech stuff down on the floor in the sleeper. It seems pretty good. I use what I had left over under my sleeping bag on winter campouts. Over that I put 1/4-inch plywood with peel and stick carpet squares. Don't do that. They don't stick very well. I am going to go back over it with household carpet. I put house carpet in my work truck. Huge difference. Quieter and keeps warmer in winter and cooler in summer. Before you go tearing everything up go, I suggest you get some carpet and cut to fit one piece to go in the cab. If you don't like it, you are not out much. Just leave the seats in cut the carpet to fit around them. 

 

[trimster]

So, bit of acoustic info. Mass cuts low frequency. For example:  rubber backed carpet squares do a bit of low & high frequency abatement.  Rubber backing (mass) plus fiber side (mids & highs).

The overpriced Dynomat targets lower frequency road noise.  Perfect for doors and cab panels. It cuts sound intrusion and passive vibration in lower frequency ranges. 

Foam, like the pads that go under our hoods, target a bit broader range of frequencies,  but bias towards lower end. It's cheap from sites like Wish. ½" thickness is a sweet spot for the range we want to target inside our cabs. You could add a bit of traditional house insulation if there's space. 

Use the 'under hood ' stuff in the walls and doors of the truck, and additional carpet on the floor. You should hear a big improvement.  Not much you can do about the plastic, reflecting surfaces.

After all that's done...you'll hear how loud the wind noise is. Not much we can do about that unless we can retro-fit a Tesla cab to our frames.

[Alie&Jim's Carrilite]

10 hours ago, trimster said:

 

Foam, like the pads that go under our hoods, target a bit broader range of frequencies,  but bias towards lower end. It's cheap from sites like Wish. ½" thickness is a sweet spot for the range we want to target inside our cabs. You could add a bit of traditional house insulation if there's space. 

Use the 'under hood ' stuff in the walls and doors of the truck, and additional carpet on the floor. You should hear a big improvement.  Not much you can do about the plastic, reflecting surfaces.

After all that's done...you'll hear how loud the wind noise is. Not much we can do about that unless we can retro-fit a Tesla cab to our frames.

What type of foam are you referring to?  Unless you're referring to material like Sound Down with the foil, rubber mat , and foam all in one.

Edited February 13, 2022 by Alie&Jim's Carrilite

[jenandjon]

Hey Trim, are you talking about putting something like this in the walls? I was going to put kilmat everywhere, but this does look like it would be better for walls. I don't think it would work in the doors though. Too thick to get behind the window on my freightliner. Maybe Volvo has more room?

Amazon.com: Design Engineering 050130 Boom Mat Under-Hood Thermal Acoustic Lining, 32" x 54" x .75" (12 sq. feet) : Automotive

[trimster]

27 minutes ago, jenandjon said:

Hey Trim, are you talking about putting something like this in the walls? I was going to put kilmat everywhere, but this does look like it would be better for walls. I don't think it would work in the doors though. Too thick to get behind the window on my freightliner. Maybe Volvo has more room?

Amazon.com: Design Engineering 050130 Boom Mat Under-Hood Thermal Acoustic Lining, 32" x 54" x .75" (12 sq. feet) : Automotive

Yes. My ultimate sound weapon is first applying a rubber frost guard for roofing . Some call it 'bitch-a-thane'. Super sticky rubber. About ⅛" thick. 

Then I put the under hood thermal stuff, over that.

The under hood stuff comes in various thicknesses. ¼ to 1". Under ½" isn't as effective. 

[jenandjon]

33 minutes ago, trimster said:

Yes. My ultimate sound weapon is first applying a rubber frost guard for roofing . Some call it 'bitch-a-thane'. Super sticky rubber. About ⅛" thick. 

Then I put the under hood thermal stuff, over that.

The under hood stuff comes in various thicknesses. ¼ to 1". Under ½" isn't as effective. 

I'm going to try that. Thanks!

[rickeieio]

Another example of why I enjoy this forum so much.  The willingness of others to help is just amazing.