2nd Gen Non-Engine/Transmission Noise reduction effort update

[Partyat33]

I am glad to see this thread is active again. The 2. 5 lb lead worked well. I covered that with a layer of sound stop. The back seat is noticeably quieter than the front. I also pulled the seats and carpet and put sound stop on the whole floor. As soon as it gets warm I will be working on the firewall and cowl area.



Dennis

 

[britannic]

Re: GSI and Drone

I had to drink a barium based liquid the other day for some x-rays; the beaker (approx 1/3pt size) was about a quarter full and felt like I was lifting a full pint plus glassware (hyperbole for artistic impact) - and the actual barium content was probably a low percentage of the total volume. My wife said I was a lot quieter for the rest of the day !



(Greg, just joking about my personal condition, no insult intended or implied about your excellent research!)

Originally posted by Lsfarm





... The foam has a barium rubber layer in it that blocks the sound. Baruim is very near as heavy as lead, I think this foam weighs about one pound per square foot... .



Take care, Greg L the Noise Nazi

 

[HEYBOSS]

I've been doing some reading on NR and getting ready for my project. I'm considering gutting out the whole interior including dash and all.



As anyone tried line-x the interior and will it work? I was thinking doing the line-x thing and then GSI over that. One problem with foam up against fire wall inside cab may be clearance to reinstall dash!



On the other hand it may be cost effective to use the NK instead line-x and easier to apply because I won't have to mask out every thing. Don't want to use lead due to weight as I'm running very close to weight ratings with the 5er.



PS, I have the bad 2000rpm drone that drives me nuts, that's my main concern but, will also be nice to have a quieter truck.

 

[Lsfarm]

Pulling the Dash

Brittanic: no offense taken LOL. I hope the 'barrium cocktail' was tasty!! Yum Yum.



Heyboss, pulling the dash is a major pain, I wish I could justify it just for soundproofing, but I can't. I'm afraid of creating more squeeks and rattles than I cured if I pulled the dash off, or just out of the way to install foam or NK.



If you are gong to pull the seats, carpet and door panels off you will have plenty to soundproof. You can do the firewall from the engine side, it is a real PITA, but less so than pulling the dash.



I'm waiting for a 'magic treatment' to be invented: something like a carwash soap additive,, special fuel treatment, or air freshener treatment to be done in like 10 minutes that drops the interior noiselevel by 15 decibels. LOL.



OH!! there is one: $40K for a new '04 truck!! As much a I hate noise, still not worth it. LOL



I work on and drive a lot of our CTD trucks, some aren't too bad, but some give me a headache within a few miles. Every truck is different. Even with all the work done on my truck, the noise can get on my nerves on a long trip. But the difference is that most of the noise I have now is wind noise, and road or tire/pavement noise. The Cummins is mostly tamed.



Take care, Greg L. The Noise Nazi

 

[GLASMITHS]

Noise Killler

I agree with Gregs' post on removing the dash. You would do more good by insulating the firewall and down in the vent (remove the plastic shroud) the underside of hood where it meets the engine compartment gasket and also on the front of doors. The NK could be painted if the grey color did not suit you in the engine compartment. Also another area is the exhaust down-pipe. I used the turbo wrap from Summit. If you use that you can get some cheap stainless steel clamps from Home Depot, from the plumbing department.



Good luck - Now a little more air

 

[zues]

I have been working on hot rods and found this new material that reduces heat and noise. It is a ceramic spray on coating.



Here is there website



https://ssl.nshosts.com/coolcarllccom/order_1.asp

 

[HEYBOSS]

Jcw-GSI

Does anyone know which pn is the Jcw same as Gsi? I see at least four different numbers on previous posts



Glasmiths, will two gallons NK be enough to do interior, doors and wall? How thick is this stuff when dry?



I'm still going to pull dash, I like challenges will do the NK and GSI, then oil pan and valve cover and go on from that.



TIA,



Fred.

 

[GLASMITHS]

Noise Killer

Heyboss



To answer your question, yes. As a matter fact one gallon will get the inside of cab. I purchased one gallon, put 2 coats on rear wall and 2 coats on floor, and still have a little left, maybe enough to do one door. A word of caution. It needs to be warm in the cab (I used a drop light) AND make certain you protect the bolts that stick up for seats and plug the bolt holes. This stuff gets lite cement and you will need a thread clean out if it dries, trust me Juist follow the directions as far as thickness goes. My opinion would be that 1/8th to 3/`16th would be the maxium effective thickness. More is not necessarily better. Then 1 layer of 1/2" of the GSI from the Co that makes it or jcw, which ever is cheaper. Pay attention to shipping charges. It is the same stuff. Also I pulled the pimpy oem stuff off the carpet so I could put 2 layers on the passenger side. Good luck

 

[OTRPU]

OK, I've read the whole thread. Sort of chuckled to myself cause I remember back when I first got my used 99 Ram. Thinking to myself how quiet it is compared to my 96 PSD 350. Where does the 99 come in on the noise race compared to both earlier and later years. Maybe this noise reduction effort is something I should seriously consider, you see I live in this truck and drive it on average 10 hours every day. I still think the Ram is quieter than my old PSD, maybe I'm kidding myself. But my apples may come from a different barrel. The rear seating and the back wall of my cab has been removed and a large fiberglass shell installed on a frame that's been extended 4 feet. Maybe this accounts for it being quieter. I don't turn the radio up at all in the Ram, in the Ford I set it at at least 3/4 full volume.



Cheers,

Steve J.

 

[HEYBOSS]

Finally

I got around to my NR project. Removed seats and carpet. Brushed on the Noise Killer, two coats back wall and floor. Did GSI from Jc on back wall and passenger floor. Didn't have enough to finish hump and driver's floor Anxious to see the results, put everything back and... ... ... ... ... ... . Wow, what a difference it made.





The radio can be at a lower setting and it sounds nice.

Just ordered another four rolls of GSi and another gallon Noise Killer for the rest. Used 3m 77 spray, just be careful with it. You have about . 5 seconds to get it right.



Now I'll be taking out the interior again to do driver's floor and hump and will attempt to pull dash to do firewall.



Question on doors. What's the best and most affective way? glue the GSI on door panels or inside door skins?



Thanks to all and will keep updated.

 

[Forrest Nearing]

I would glue straight to the doors' sheet metal... that's what I plan to do on my next round of noise reduction!



Forrest

 

[Bob4x4]

The inner firewall already has insulation on it but your liquid coating under that may help



Bob

 

[Forrest Nearing]

the inner firewall doesn't have anything actually glued to the sheetmetal... adding density to the metal will really bring the resonance down.



Forrest

 

[GLASMITHS]

Update and reply to above post

You are correct about HOW the material is attached. If it is a mat type noty glued to the metal the noise reduction is not near like if it is glued; remember that sound is a viberation. So. According to my wife who has normal hearing, the best improvement was when I applied one layer of GSI to the floor UNDER the cab; and from the firewall to rear of transmission. As well as wrapping the exhaust from PAC Brake to resonator. We just returned from our annual trip to WV and it was much more enjoyable; running thru the mountains in 3rd direct at 26-2800rpm. Before about 2300 was the outside limit for long periods. The new HX 35 made about 100* difference in egt. On a 6% grade at 28# boost it was 1150-1200*. Going down the other side with the t/c locked it would be 250*

 

[DaveN]

I've seen some questions about the how and why lead works - here's an analogy to help you understand the vibration.



Sound IS a vibration of air molecules. The noise you hear is transferred from your engine or exhaust through the air to the cab of your truck. The energy carried in vibrating the air is transferred to the cab walls. Microscopically, that energy then vibrates the cab (it moves). That then moves the air inside the cab, hence you hear the noise. The more it vibrates, the more air is moved, the more your eardrum vibrates, and the louder it gets.



So - how do you eliminate it? If you can minimize the amount that your cab vibrates, then that transfers less energy into the air inside the cab. So the lead sheeting helps. How?



Well think of it this way. Lets say you weigh 200 pounds, and you and the 7 year old neighbor kid decide to swing on a swingset. Your wife applies a five pound force to you while you're sitting on the swing. You move, and swing back and forth maybe six inches. She applies the same force to the 40 pound kid, he swings back and forth maybe 12~15 inches. So the same energy applied to a weaker vibrating system (the 40 lb weight on a swing) results in more movement than is does a stronger system (the 200 lb man). So when you add a square foot of lead sheet to a square foot of sheet metal, you may be adding say 25~30% to the weight per square foot. The exterior sound level is the same, the same amount of energy is applied to your cab wall. But if it weighs more, then it moves less. This means that less vibration intensity is available to move the air inside the cab.



One other way to accomplish this is to stiffen the vibrating system. This is done by adding strength ribs to it. But this isn't practical in this application, or in this case probably not as effective.



The foam works because it disrupts the moving air, it acts like a cushion. The noise is still transferred, but it's confused (not direct) and therefore the intensity of it is reduced, it acts as a shock absorber. It also adds a small amount of mass to the system, and helps for reasons above.

 

[gocirino]

Check out this sound deadener paint. It converts soundwaves into low grade heat. Also ETR Diesel sells a blanket for the AFE air cleaner that claims to reduce turbo whine.

http://www.silentrunning.us/

 

[GLASMITHS]

Check out this sound deadener paint. It converts soundwaves into low grade heat. Also ETR Diesel sells a blanket for the AFE air cleaner that claims to reduce turbo whine.

http://www.silentrunning.us/

Have you checked with them regarding the price per gallon?

 

[gocirino]

I might be wrong but I think it goes for $125/ gallon. A bit pricey but it's technology that the space shuttle uses. Maybe too good for a truck application.

 

[GLASMITHS]

Thats about twice the price of "Noise Killer" that I used. It is all about encreasing the mass of the metal, to stop the viberation. If I could do it over, there would be a coat of Durabake put on the bottom beforfe the foam. The Durabake comes also without the rough stuff and goes on very smooth. It might not help all that much, but every little bit helps.

 

[Forrest Nearing]

update on the roof:

it's been a few months since I put lead sheet on the roof...



I did it to help out with the stacks, and it helped a lot.



but I have since removed the stacks, and now I have had the 5" straight pipe back on for a while now.



I drilled 1/4" holes in the pockets in the roof, and shot tubes of caulk and liquid nails up there (baiscly, tubes I had laying around) and then put a layer of 1/16" lead sheet up there using Liquid Nails "Paneling Adhesive" to stick it. I doubled up on all the large rectangular sections, and I trippled up on the areas that resonated the most when I hit them w/ a closed fist.



last week, I spent 8hrs in the truck with about 8,000lbs hooked up, and the resonance was an absolute non-issue... it hasn't been any big deal empty, but I figured this was about as big a test as I was going to get. 75-80-85mph, no problems.



so if you've killed the noise in the rest of the cab, get some goo on the roof, it makes a nice difference!



now all of my resonance is coming from the downpipe area of the firewall... it's not bad at all. I'll live with it till I can get some twins on there.



Forrest