Recipe for a quiet(er) cruiser

[Sully]

First, a few disclaimers. One, while discussing this project with CruiserDan, he mentioned that the Land Cruisers, when first produced, were listed as the quietest vehicle ever tested by some magazine (I can’t recall which one). I believe that I have improved on the factory insulation. The truck is now so quiet that I can barely hear the engine with the radio off and road noise is minimal despite not having done the doors yet. Second, I went to greater lengths than most probably will since I dismantled the dash and replaced the factory firewall insulation. I probably wouldn’t recommend this if it isn’t necessary. In my case, it was due to coolant leakage. Also, I hope to convert over to a diesel motor in a few years and wanted to do a pre-emptive strike on the extra noise it will generate. Third, this vehicle is a daily driver/kid hauler, at least in the wintertime. Gas prices willing, it may get some good summer driving time. While I hope to do some off-roading/expedition-style wheeling in the near future, that is not this vehicle’s primary function and I approached this project as such. Fourth, I am not affiliated with Second Skin Audio, www.secondskinaudio.com but I highly recommend their products. They are quite easy to work with, even in temperatures barely above freezing. They have excellent customer service and the owner, Anthony, is quite knowledgeable and willing to spend time discussing various aspects of the project.

 

[Sully]

Step one: Gut the vehicle.
At a minimum when doing this project, I’d recommend removing all the seats, carpet, under-carpet insulation, trim panels, subwoofer/amp, and the center console. If you do decide to remove the dash, have the FSM and electric FSM, take LOTS of pictures, and put the various fasteners into separate labeled baggies. Do not get on a roll and go crazy taking things apart, so that you end up with a huge pile of screws and bolts with no idea where they all go later (as I did). Also, don’t wait nine months to reassemble everything. Parts and memories disappear. If you do the dash, consider replacing the coolant hoses on and around the firewall since you’ll have them apart anyway. There is a silicone kit for some of them from http://www.1fzfephh.com/. You could also replace the factory sardine can fasteners with constant tension clamps if you’re so inclined. My local NAPA carries the Breeze CTCs for around $5 each, so I did. You could also do the AC receiver relocation mod since you’ll have the system evacuated/open and have to replace the receiver anyway. I didn’t yet because I’d already ordered the LC receiver from Dan before I read the thread on relocation.
While you have the carpet out, take a few minutes to remove the old jute insulation from both the underside of the carpet and the bed of the vehicle. Scrubbing with Scotch-Brite pads and Simple Green removed most of it from the vehicle. It will all get covered in due time. I just pulled off as much as I could from the carpet and left it at that. This might be a good time to really clean the carpets too.

 

[Sully]

Step two: Base layer in back
For the base layer, I used Second Skin Audio’s Damplifier (http://www.secondskinaudio.com/cgi-bin/index.cgi?p=ps&pg=1) It is a butyl-rubber compound with an aluminum backing and comes in 1x2ft sheets. I installed this when temperatures were in the 40s and had no problems with the material not sticking. I chose this product primarily because it has the dual properties of sound dampening and heat reduction/reflection, and because its butyl rubber design eliminates the odor that some asphalt-based sound deadening products have been known to emit under warmer conditions. There is a thicker type of Damplifier available (Damplifier Pro), but I didn’t think it would be worth the extra expense for my purposes. Also, I was concerned about the overall thickness of the insulation. More on this later. I took this all the way up to the ridge where the front seats attach. I also installed it into the rearmost body cavities and on the fender wells. For this step, I used approximately 40 square feet of Damplifier. I was fanatical about reusing scrap pieces and I think it paid off in reduced material costs.
A couple of notes here. Make sure that you don’t cover any of the many screw holes. Also, stay off of the raised sheet metal humps where the seats and/or seat rails attach. If you should happen to get some of the rubber on your clothing, get it off quickly or it will stick. A night in the deep-freezer and liberal application of Goo-gone did wonders for cleaning it off of my jeans. A better approach would be to not wear one’s favorite jeans for this job.

 

[Sully]

Step three: Base layer in front
For the front base layer, I used a product called Spectrum Spray (http://www.secondskinaudio.com/cgi-bin/index.cgi?pg=2&p=ps) This was an interesting product. It is a liquefied rubber that dries to a semi-solid state. It goes on blue and, as it dries, turns grey. I bought a gallon, and wasn’t sure exactly how much this would cover. My primary concern was to cover the firewall. Once that was accomplished, I moved backwards and coated the floorboards and tranny hump. I then did a second layer in each of these areas. Both layers were applied with a paint brush. According to the manufacturer, this can be sprayed on, but I thought that it might be a little more trouble than it was worth (the company owner told me that he did more installations with a brush too). The manufacturer recommended that each layer be approximately 2mm thick. As it turned out, I had enough product left over to put a layer over the middle seat floorboards. Since I had already put the Damplifier down, I had to paint the Spectrum over the top of it, but there were no ill effects. Also, all of this would be covered up in a future step.
A couple of notes here. Some minimal prep work here would be in order. Cover all the screw holes, grommets, and various studs coming out of the firewall with tape. Also, be careful of drips. If you should happen to get some on a plug, wipe it off asap. It will chip off later, but it is easier to get off sooner than later. This stuff doesn’t come out of clothing, so be warned. Finally, the manufacturer states that it cures within 24 hours. I’m assuming that that assumes more temperate ambient conditions. In my cold garage, it took up to three days for some of the places to completely dry to the touch. 1000 watt quartz lights will hasten the process for those who have to do this in less than ideal conditions.

 

[Sully]

Pictures of the Spectrum over Damplifier

 

[Sully]

Step four: Second layer in front
I covered the Spectrum in front with a layer of the Damplifier. Not much to say here that hasn’t been covered before. I could have put this under the Spectrum and I’m sure some of the engineering types here will be able to tell me whether I screwed up or not by not doing so. All in all, I have used 82 square feet of Damplifier. I still have another 80 left to do the doors/liftgate, but I’m not tackling that until the weather gets back above freezing and I get enough money together to replace the door speakers. I don’t want to have to remove the door panels any more than I have to. The only problem I encountered here was when I went to reinstall the A/C unit, I had to trim away a little of the Damplifier around the opening in the firewall.

 

[Sully]

Step five: Second layer in back/Third Layer in Front
To replace the OEM jute insulation that was sporadically placed throughout the vehicle, I used Second Skin Audio’s Heat Wave (http://www.secondskinaudio.com/cgi-bin/index.cgi?pg=4&p=ps) It is jute padding that is about 0.375 inches thick and has an aluminum foil backing. I chose this product because I wanted to replace the original insulation with something that would give some cushion for the feet of my vehicle’s occupants. I also wanted to address the problem that some have reported of excess heat coming up from the exhaust system through the passenger side. Hopefully these two layers of foil should do the trick. As I never ride shotgun in my truck, it’s never been a problem for me.
Installing this stuff is pretty easy as long as you have very sharp scissors and copious quantities of duct tape. After cutting the edges to the desired shape and size, you have to cover the edges with duct tape or else they fray quickly. Also, any internal cut-outs for bolt-holes have to be taped. On the secondskinaudio.com forum, there was some debate as to whether the foil side should be installed up or down. I opted for down because I used a spray-on adhesive to secure the product. By spraying onto the foil side only (the adhesive instructions recommend both bonding surfaces get sprayed), I was able to reposition pieces as needed, even as much as several days later. I figured that spraying the jute side would be much less forgiving. For this stage, I used three sheets of the Heatwave. It comes in 4x6 sheets. I also used a single can of the adhesive spray for both this step and the next.
A couple of notes here. Since I used a lot more of this that Mr. T did initially, it made things a little more difficult to install the OEM carpet and trim panels. I had to retro-trim several pieces in order to get the front and rear carpet sections to mate up properly. There were also problems with the steps on the rear doors and along the trim panels. I found that I had to buy new fasteners for the carpet and steps because the old ones were too worn to hold with the increased tension. I also purchased several replacement fasteners for the body trim panels. Working in cold temperatures tended to make them brittle and prone to failure. Add to this the decreased wiggle room from the extra insulation, and there were several fatalities. Along the firewall, I found that it was easier to use several smaller pieces rather than try to create a single larger piece that encompassed all of the cut-outs and variances needed. Also, I opted not to place this on the topmost portion of the dash, just below the windshield. I had another product yet to be placed and I was afraid that it would be too thick in that area.

 

[Sully]

More Heat Wave Pics from the firewall

 

[NaterGator]

I hope you're done

I just wanted to throw in my two cents as well... I am not affiliated with SS, but I have used Damplifier Pro before and I have to say it is a top notch well priced product. I used them back in about 2003 or so, but their quality even then was well above BrownBread, eDead, or Dynamat.
If you are looking for a quieter vehicle I would definitely check out secondskin.

Edit: Oh, and Anthony rocks!

 

[Sully]

Step six: Final firewall layer
For the final firewall layer, I used a product called Luxury Liner (http://www.secondskinaudio.com/cgi-bin/index.cgi?pg=4&p=ps) It is a combination open cell/closed cell foam. It feels very substantial, yet compacts nicely when needed. I had originally hoped to cover the entire firewall with a single piece (each piece is 2x4.5 ft) and I still think that it is possible to do so; however, I had destroyed the OEM rubber firewall during the removal process and therefore was unable to use it as a template. I ended up using two pieces of the liner due to some expensive cutting errors on my part.
I had hoped to be able to find replacement retention clips for the firewall insulation; however, Toyota only sells them as part of a firewall insulation kit for around $350. I then thought that I could use the same nuts that are used to retain the rear heater unit and bought a pile of them from Dan. Later, I would realize that there are two slightly different size studs coming from the firewall. The larger ones are threaded and can accept those nuts; however, they are used to retain the heating/cooling system. The small ones that are designed to hold the firewall insulation are simply ribbed. I never did find an acceptable clip and ended up using the spray adhesive to secure everything. If anyone finds that they need a few of the nuts, PM me and I’ll be glad to send you some. I had to cut the liner into several pieces because the weight made it impossible for the adhesive to properly secure a larger piece. I also found that I had to trim this around the A/C firewall opening and the air intake opening when trying to reassemble the dash.

 

[Sully]

Final thoughts
All told, with shipping, this cost me around seven hundred-fifty dollars in materials. That includes the stuff from Dan, various other failed attempts at firewall clips, a throw-away paintbrush, and a large roll of duct-tape. I’d be curious to know how much of a difference this would make without doing the firewall. I’m also looking forward to getting the doors done and getting some decent speakers in it. Right now, I’m pretty impressed with how little I can hear. There is still some noise from the doors and there’s not much anyone can do about the wind noise from the windows. There is also another product that I may investigate at a later date. It is called Rattle Pad and is designed to alleviate trim panel rattles. Since I reassembled the dash, there seem to be a couple of them. Of course, they may have always been there (like the previously mentioned wind noise) and I just didn’t notice them before. Sorry this was such a long post. I’ll do my best to answer any questions I might have missed.

Respectfully submitted,
-Sully

 

[DuManchu]

Wow. Just, wow.

Great job!

I don't think I'll be doing this, but I'm sure its worth it to those who want a quite vehicle.

 

[MJADDICTION]

Excellent, thanks for the write up. Did you happen to price new carpet?

Thanks.

 

[knorrena]

Nice work. Your attention to detail is admirable. I have similar plans, but not to the same extent. I have a but a single compaint: now passengers can hear each other fart - probably even little squeakers.

Karl

 

[DTAYLOR]

Excellent work..

Sully,

This will certainly buy you a front table seat at the NAOT (National Association of Over-Thinkers) ball and mid-year picnic. (I host both, for I am their leader).

You have done yourself and all of us proud. I solute you, sir.

DTaylor
NAOT President

 

[Hayes]

Holy s***e.

Strong work.
Want to do that to mine?

 

[stayalert]

NICE WORK!!!! (shouting so you can hear me)

Mine seems pretty quiet but I have to stick these in my ears....

Seriosly very nice - great way to investigate for and head off rust I wuld think as well.

 

[Miescha]

Wow - very nice! or should I say "very nice" so as not to hurt your ears .

I'd love to do it, but haven't the time or motivation (especially in the cold).

Keep us posted on how it sounds once you have the doors done.

 

[450 DUDE]

MAN!!!

I think this belongs in Hard Core!
Because its just that, NICE !

But I now feel totally inferior because Im only doing 1/16 of your job.



ken

 

[robmir]

A year after I bought in 1993 my FZJ80, I removed all door, rear quarters and rear uper and lower back door covers and applied from accele a sound dampening material very similar to Dinamate which came in rolls, the kind which has a removable film to expose the sticking side. After applied (inside on the outer body wall, with the windows in the up position and not between the door and the trim), it was hard pressed against the wall with a small roller.

I did notice right away a sensible improvement, my cruiser was very quiet specially when driving inside tunnels. Also the sound from the door speakers (which of course I replaced with better and larger units) was better and without any rattling.

I salute you for your excelent work and sugest you to go ahead and do something also with the doors, rear quarters and the back doors !!!!!!!!

By the way if the roof headliner is removed it could be also a great idea to insulate it !!!!!