Head is spinning trying to figure out sound dampening

[Rushthezeppelin]

So I just got my order of vinyl flooring from ACC today and I figured the obvious right thing to do while installing this is sound deadening the floor (and perhaps I'll slowly tackle other areas in the future). All the threads I've looked at don't seem to make things super clear on what I would need.

So I don't blast music, I'm not an audiophile. Most of the time I just listen to youtube podcast style stuff and occasionally some classical or an audiobook. However I would like to do some good bang for the buck in quieting up this truck, they certainly were a little noisier 25 years ago compared to now (I'm sure the whole body on frame also has something to do with it compared to unibody vehicles). I also wouldn't mind it actually having some insulating effect whether it's making my A/C work that much better in the summer or having the truck stay warmer in the winter when I'm camping in the back. Right now I figure since I only have flooring for the passenger area of the cab I'll just tackle that.

Would just getting the 36ft2 pack of siless 80 mil accomplish what I'm looking for more or less or do I need to add stuff to that? Ideally I would like to stay around 100 bucks at most but if I'm already in there and it makes sense to spend a bit more I'm okay with that too. I'd guess I'm also in the camp of I would want to avoid any of the asphalt alternatives for the offgassing (am I correct in thinking that the people who go super budget and buy the roofing stuff are using asphalt as opposed to butyl?).

Appreciate the help and wish I didn't have to post this but my research so far in the forum and in other places doesn't seem to be clearing this stuff up for me right now.

 

[gamefreakgc]

Did you read this one? I used this as a template on how I did mine. Even ordered from the same company that now unfortunately is out of business. 3rd Gen 4Runner: Sound Deadening Tutroial & Body Panel Removal.

The worst area for road noise is actually the rear cargo floor. I ended up putting 4, yes 4, layers of sound deadening on the cargo floor. Rubber matting, foam, rubber matting, foam. Next after that is the rear wheel wells. You'll want 100% coverage on both of those areas. Finally the front doors. Start there and you'll notice a difference right away. I recommend also getting a foam as the rubber/butyl matting helps dampen vibrations but does not always keep the sound out. That's where the foam comes in.

 

[JZiggy]

Siless 3-in-1 worked well for me. It works as a vibe dampener and acoustic foam.

 

[Rushthezeppelin]

How well does butyl foam on it's own work? I know combining foam with the solid sheets is better but is the foam alone still going to be a good bang for the buck?

 

[gamefreakgc]

How well does butyl foam on it's own work? I know combining foam with the solid sheets is better but is the foam alone still going to be a good bang for the buck?

They both serve different purposes. The best bang for your buck is indeed the butyl rubber mats. It dampens the resonance. Think of like when a gong is rung and the loud sound resonates and crashes in the gong well after it was struck. Put your hands on it and the ring turns into a thud. No resonance. Doesn't require full coverage either, usually 50%, except for that super noisy rear cargo area!

The foam is like an earplug. Much like the foam ear plugs you'd use it plugs up holes, gaps and openings to muffle and quiet the sound down. Without the mats they will still resonate though. Does require 100% coverage to be most effective.

Both together is best. If only one rubber matting is best.

 

[Rushthezeppelin]

So I just ran across this video How to Sound Deaden Your Car. How Quiet Can You Make It? Results Before and After. - YouTube. This is just the most clear and concise explanation of how all this stuff works and confirms that I chose well going with the Siless 3in1(ordered 50ft2 for now). Hopefully this helps someone in the future.

 

[gamefreakgc]

If you are going for high quality audio, be careful how much you put right behind the door speakers. The mass loaded vinyl will absorb sound too much and cause you to lose some frequencies making the music sound flat. If you can peel off the vinyl and leave just the butyl and foam that's more ideal.

 

[Rushthezeppelin]

If you are going for high quality audio, be careful how much you put right behind the door speakers. The mass loaded vinyl will absorb sound too much and cause you to lose some frequencies making the music sound flat. If you can peel off the vinyl and leave just the butyl and foam that's more ideal.

As I outlined in the OP, I'm not an audiophile. I just want to reduce road noise and get some thermal insulation as a bonus. Only even worrying about this as I'm replacing the passenger carpet with vinyl (and will do the cargo area at some point) so it's a might as well do it while I'm in there thing. Not worrying about any other areas atm, but I might keep that in mind if and when I do the doors. I really would like to reduce road noise though, this truck is super noisy between not having much sound deadening from the factory, being 25 years old and having AT tires.

 

[BigDummy]

For people who have done a thorough sound deadening, how much of an impact is it really? Has anyone here measured before and after? I've had my 4runner for nearly 20 years and am trying to decide if its time to finally mod it or if its time to sell it.

 

[gamefreakgc]

For people who have done a thorough sound deadening, how much of an impact is it really? Has anyone here measured before and after? I've had my 4runner for nearly 20 years and am trying to decide if its time to finally mod it or if its time to sell it.

I don't have a decibel meter but the result is very significant. By far the worst sound bleed is over the rear wheel wells and rear cargo area floor. One sound installer commented that the 3rd gen cargo area is one of the most resonate spots in any car he'd ever worked on in his entire career.

At the time I had an aftermarket Borla muffler installed that was a bit louder than stock. After sound deadening just the rear cargo area and the doors (I didn't do the roof or under the foot wells) it was as quiet inside as stock until I rolled down the windows. It was worth it for me as I was looking to quiet down the interior for better sound quality when doing long drives. It also allowed my wife and I to have very casual conversation in a lower tone as we could hear each other much better. Then I threw caution to the wind and put a 3" exhaust will a glass pack muffler on for more power and it is louder than ever. C'est la vie.

Some things that may make sound deadening not worth your time:

• Keeping the stock sound system as it is not quality enough to warrant sound dampening and deadening
• Large AT/MT with aggressive treat patterns as some are so loud it will not be enough to quiet them
• Noisy kids in the backseat that ruin any peace and quiet you might have gained from sound deadening

 

[Rushthezeppelin]

I would definitely say it was surprising just how much doing the passenger and cargo floor was. I've been extremely pleased and definitely looking forward to doing the doors in the future and will probably pull the headboard and do the roof eventually. Also I highly recommend the 3in1. It cut down on install time by A LOT. It's a little bit of a compromise on material thickness but yeah like I said, I'm super pleased with the result.