Shhhhh Quiet Please (3rd Gen Sound Deadening Project)

alphyn

New member
I guess this very well could be my first real mod on my 4runner other than putting on a rack or getting FJ Cruiser Trail Edition black wheels. So, a little bit of background before I start. I'm kind of weird. I only drive manual transmissions, and after searching high and low for a few months I came across my 1999 Highlander, black with grey leather interior. I purchased it from another member on T4R. Hooray for the Internets. Boo on Toyota for stopping production of manual transmission 4runners for the US in 2000.

I read a story one time about an elderly man in Canada that went to rent a car and the rental agent had to teach him how to drive an automatic because, although he was in his 80's, he had never driven an automatic before. Only manual transmissions his whole life. I could be that guy. I'm that weird.

I've decided that my 4runner pretty much has to be my forever car, and very well may be the last manual transmission 4x4 I ever have the pleasure of driving. That means I'm entitled to spend stupid amounts of money on a vehicle that is 14 years old, and has a street value of less than $10k, right?

First (money sink time waster) project up is turning this thing from tin can into silent vault. Right now with the Highlander suspension, I hear every boom, bang, clank, and shudder the road has to offer. Toyota did a really crappy job of sound insulating the rear half of 4runners, and the stiffer suspension adds to the drama. I'm going to fix that.

If you have any suggestions, questions, or comments, please let me know. I'm not an audiophile, but am pretending to be one at the moment. Your help will be much appreciated. And I also have no experience doing this, so I'm expecting the results to be amateurish and comical (or totally awesome).

I'm dividing this process into 6 steps as outlined below. I will create a post for each step. I will document how I perform work OR provide links to where I was able to learn how to execute whatever steps are necessary. No reason reinventing tutorials that are already available.

Step 1: Baseline Testing
Step 2: Material Selection
Step 3: Vehicle Prep
Step 4: Installation
Step 5: Vehicle Reassembly
Step 6: Performance Testing

Reference Posts

Vendor List
Soundproofing Build Threads and Tutorials


Also a quick shoutout to Skidmarcx. His soundprofing project was inspirational and can be found here.
 
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Step 1: Baseline Testing

Purpose: Determine performance of stock sound deadening materials and methods by testing vehicle under normal road conditions.

Methodology: Use a sound level meter to record decibel level readings under the following conditions

Engine - No Load


Engine - No Load
Details: Using a sound level meter, 5 measurements were taken. Measurements included minimum and maximum decibels recorded over a 5 second period of time. Control consisted of measuring ambient noise inside the cabin with the vehicle turned off an all windows up. Engine was turned on and warmed up to record idle sound. Results are as follows.

enginenoload.jpg


It is interesting to note that the engine is actually quieter at 1500 RPM than at idle (700 rpm). Also, the engine is quieter at 3500 RPM as opposed to 3000 RPM. Guess the engine balances itself out slightly better at those RPMs.
 
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Step 2: Material Selection

Purpose: inventory and cost of all materials used for project.

Dampening / Resonance Reducing Products

MLV (Multi Layer Vinyl)

CCF (Closed Cell Foam)

CLD (Constrained Layer Dampening)

Misc. Supplies and Installation Tools


Note: Thanks for all the suggestions and interest in this thread. I'm going to create an inventory of potential vendors and in a reply post below. Keep all the suggestions coming!
 
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Step 3: Vehicle Prep

Purpose: document all activities required to prepare vehicle for sound deadening material installation.
 
Step 6: Performance Testing

Purpose: Determine effects (improvements, detriments) of using sound deadening material over stock.
 
very cool.

are you going to do the $900 is parts and materials (semi-pro or pro) way?

In 2007 I did my whole interior with rubber roof liner (per Yotatech articles) and it has worked great. The cost was about $140 in materials.
 
very cool.are you going to do the $900 is parts and materials (semi-pro or pro) way?

The goal is absolutely to spend way too much money. I'm still investigating tons of options on materials. I came across some lead core flooring materials from Cascade Audio Engineering. Evidently that retails for about $230 for a 12 sqft roll. But yeah, tons of options I'm looking at right now. Analysis paralysis.
 
Excited to see your progress! I did this about 6 months ago on mine... Spent around $400 using Second Skin... Have fun!
 
I will hopefully have my runner rolling again by the end of the month. I will post up some "after" spl measurements when I do, so you can get a feel for the effectiveness of the materials I used.
 
Subscribed for updates. Im mostly curious how much the project ends up being. I would LOVE to do this, but 900.00 is way steep for me. But, if its around 300.00 then I think I could talk myself into it.

Just as you said, my 4Runner is my favorite vehicle Ive owned, expect to drive it for a long time and even plan on giving it to my kid (maybe, I might still keep it) and he is only 1.
 
I use the Stinger sound dampener for $120. Was enuff to do the roof and the 1/4's and some of the floor. I am planing on buying another box of it to do the rest of the floor board. But from what I can tell the noise coming from the roof and rear half has gotten quieter.
 
Purpose: Determine performance of stock sound deadening materials and methods by testing vehicle under normal road conditions.

Methodology: TBD

Results: TBD

If you have a smart phone, there are decibel meter apps that you can download. Maybe this will help in determining before and after comparisons. Good luck with your project!
 
REFERENCE: Vendor List

There's a bunch of great suggestions coming in. I will start a running list of vendors and products here.

I will be dividing this list up between automotive dampening specialty companies, such as Dynamat, and general sound dampening vendors. Many sound dampening products seem to be multi-use. For instance, MLV with a layer CCF is commonly used in sound dampening in homes and is essentially the same product sold by Second Skin as Luxury Liner Pro.

Vendors

Automotive Specialty Dampening

Second Skin (Vehicle Sound Deadening Materials for Noise Reduction, and Thermal Insulation.)
RAAMaudio (RAAMaudio - Automotive sound deadening products)
Dynamat (The Official Dynamat Website)
Cascade Auto Engineering (Cascade Audio Engineering – Sound Damping and Sound Blocking)
Lizard Skin
Fatmat

Non-Automotive Dampening
Soundaway
Sound Isolation Company
Acoustics First
Nuclead - Lead Sheeting Supplier
Products

MLV (Mass Loaded Vinyl)
Second Skin - Luxury Liner

MLV with CCF (Mass Layered Vinyl with Closed Cell Foam)
Second Skin - Luxury Liner Pro

CCF (Closed Cell Foam)
Second Skin - Overkill
Second Skin - Overkill Pro
Dynamat - Dynaliner

CLD (Constrained Layer Dampening)
Dynamat - Dynamat Xtreme
Dynamat - Dynamat
Second Skin - Damplifier
Second Skin - Damplifier Pro

Product Reviews
CLD Performance - This Will Make Your Head Hurt! 21 plus pages of a guy who went through painful and excessive means to sort out the best CLD on DIY Mobile Audio forums.
 
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If you have a smart phone, there are decibel meter apps that you can download. Maybe this will help in determining before and after comparisons. Good luck with your project!

Yeah, I figured there might be an app or two that I could leverage for that. Hopefully they have an app that will record decibel volumes over a few minute period. It might get a bit tricky trying to record decibel levels as I drive along. Might have to recruit the girlfriend. All of a sudden this has become so scientific.
 
i dont know if you have seen my basic sound deadener on my build. im kinda excited to see what you do here. there is so many options you can do when it comes to this type of mod, i did quite a bit of searching and found the best that worked for what i wanted to do at a super cheep price.
here is the link.

its just about all the way to the bottom of the page. http://www.toyota-4runner.org/3rd-gen-t4rs/128879-shoots-build-thread.html

Ah! Time for another inventory of threads. Thanks for the heads up. I'll head on over and check out what you've done. But yeah, way too many options. Makes the head spin at times. I was at a local audio shop and they quoted me $700 to build a custom sub box, amp, and sub that fits into the right rear panel in the cargo area. So, then there's also the stereo upgrade to consider. Lots of things to think about.
 
Ah! Time for another inventory of threads. Thanks for the heads up. I'll head on over and check out what you've done. But yeah, way too many options. Makes the head spin at times. I was at a local audio shop and they quoted me $700 to build a custom sub box, amp, and sub that fits into the right rear panel in the cargo area. So, then there's also the stereo upgrade to consider. Lots of things to think about.


i still have about 20sq ft of stuff left and i need to do the roof. when i turn the subs up, it shakes the roof and it slaps against my smaller 3 rails that lay on the roof outside. but i have done everything else. (just dont want to pull the head liner.
 

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