M35A2 Sound Deadening Project

The stock water pump makes a lot of noise and I'm told consumes 13 HP.

I installed a Spal (Google Spal fans) electric fan to replace the stock fan and it made an appreciable difference. The project was covered in one of my posts.

Just wear a good set of ear plugs and forget about it.

Thanks for the info on the electric fans. I checked out the website and I'm thinking that may also be a good upgrade especially since the fans are 24V. Personally, I've never liked mechanical fans much anyway since they are always operating even when not needed and the old metal ones have been known to remove fingers in an accident. Appreciate the help.

The foam supplied in the arctic kit looks nice and helps a lot.

Bill

McMaster Carr has some nice 1" thick neoprene foam as well as other foams that comes in large sheets. I expect this could be used on the inside rear of the cab to deaden quite a bit of sound and stop the drumming from the rear sheet metal. skin it over with some solid highimpact plastic sheet and you're good.

One thing you have to be careful with when using soundproofing like dynamat or neoprene foam is condensation between the material and the vehicle shell.This can be a major pain and cause rust faster than you'd think.
just make sure you are glued tight to the sheet metal with no air pockets.

just came to me... how about using something like under body coating. They are designed to reduce noise, insulate slightly, prevent rust, and are usually paintable, so there you can retain a stock look yet gain sound suppression as well as a little extra rigidity. From what I have seen it is simmilar to spray in bedliners.

rattlecan6104 said:

how does that muffler sound, I've heard the napa muffler and I couldnt stand the sound at all. a video would be great if you can.

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Found a video of the napa muffler for reference...
[media]http://au.youtube.com/watch?v=itzObnq4pIw&feature=PlayList&p=3F34330044DA4EA9&playnext=1&index=31[/media]

rattlecan6104 said:

just came to me... how about using something like under body coating. They are designed to reduce noise, insulate slightly, prevent rust, and are usually paintable, so there you can retain a stock look yet gain sound suppression as well as a little extra rigidity. From what I have seen it is simmilar to spray in bedliners.

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Those work well, did that to my old F350 using RhinoLiner, really quieted things down, and best of all, no condensation!

Good point about the condensation (yes, it rains in NW Washington ) I think I'm actually going to strip the entire interior and get it professional done with Line-X. Very nice stuff if anyone's seen it. I was going to do the bed area with it anyway so it only makes sense to take care of it all at once.

That ought to solve the moisture/rusting problems that would occur. After that's done I'll actually lay in the sound deadening material. I'm hoping the Line-X will kill the rattles and vibrations and the rest of it will knock down a good part of the noise.

Anybody have any idea how much adding a muffler reduces the overall noise level? I'm going to run my exhaust out to a rear dump near the tailgate but I'm just curious.

Hey Ross, have you gotten any quotes on the Line-X for the bed?

There is a gut here who built a bobbed deuce and deadened it. He put pics up an all. Look for diablo and bobbed.

The biggest improvement to sound proofing a deuce is not found in the amount of matting or insulation crammed into the cab area. Its in the over all treatment of the sheet metal through out the truck.

When I did Diablo I went absolutely nuts but in the end of the project I found it was more about the undercoating that I put into the hood, fenders, cab, doors etc than it was about the matting and insulation inside of the cab its self. Adding the rubber to the over all truck added density there for removing the residence (sound can no longer travel and resignate)... Another big difference was made in installing the hinge kits I make which get rid of the metal on metal contact adding nylon in between... Especially the hood hinges!!!

When people are standing outside of the truck listening to it run they often look to the exhaust and then ask where in Sam's snot I could have possibly hid the muffler in the J pipe assy... There is no muffler... Its just the hood, fenders and doors stopping the noise they use to amplify and redistribute.

That is interesting.. I never thought about the resignate issue. That would enplane why new semi trucks are quieter. The whole cab rides on airbags compared to the frame. I wonder if you could put airbags under a mil truck cab, or would it mess things up.

Thanks Devilman, I read the entire post on your Diablo build; VERY NICE That makes sense with what you're saying about the resonation issues. Line-X applied inside the cab will hopefully address that issue as Line-X is a rubber based product or something with similar properties.

What type of undercoating product did you use on the underside of the hood, fenders etc? I may have missed that in reading the Diablo thread. How much noise were you able to successfully cancel out with all the work that you did? I know you've got quite the stereo setup in that truck but do you still feel the need to wear hearing protection to guard against the engine/truck noise?

Thanks everyone for the insights into this, Ross

Sorry, I forgot the address the question about the cost of Line-X that was asked prior.

A couple of years ago I went in to a shop to ask them how much it would be to coat the entire inner tub of a 60's era FJ40 Landcruiser. The guys in the shop were very flexible and said they would do the job for right around $300 as long as I was willing to prep the truck. For this, they even offered me space in the shop to remove/unbolt everything from inside the cab.

As for prep, they told me they didn't want everything stripped down to bare metal before they applied the Line-X. Any/all loose scale and rust needs to be removed but good, solid paint just needs to be roughed up with very course sandpaper so the Line-X will get a good bond.

So, I never did get the truck Line-X'd because shortly thereafter I ended up rolling it (several times) while rockcrawling. I looked at the poor tub and decided that it only made sense to get it coated after I fixed my screwup. So, now I'm in the process of designing a rear tube frame/body to replace the damaged tub from about the rear of the driver's seat area back. Too many projects to count

Line-X will stand by their product and fix it free for the time period that you own the truck. I've got a friend who has it installed in the bed of his pickup and the only problem/failure was about a dime sized chip which was fixed. If anyone has compared the two, Line-X has a much more consistent texture compared to Rhino Lining which is why I selected it.

So, If my Deuce is all prepped when I bring it in, I'm guessing it will run right around in the $200 range for the cab and $300-$400 for the bed. When I talked to them, they were figuring cost mostly based on how much product was required to finish the job.

Hope this helps somewhat, Ross

devilman96 said:

The biggest improvement to sound proofing a deuce is not found in the amount of matting or insulation crammed into the cab area. Its in the over all treatment of the sheet metal through out the truck.

Another big difference was made in installing the hinge kits I make which get rid of the metal on metal contact adding nylon in between... Especially the hood hinges!!!

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Are the nylon hinge bushing kits still available? I would really like to get rid of some of the rattles, squeaks and chirps from the various moving panels and brackets. I think I can just tighten up the bolt on the one below.

https://youtu.be/IRQQ2IKlYqc

Another big noise maker I've noticed is the panels above the fenders, they have rubber insulators to prevent metal to metal contact...but only from movement inwards. When the panel moves outwards it rattles like crazy.

I don't mind the engine noise but I can't hear it for all of the rattles and squeaks, makes me nervous because I think something is getting ready to come apart on the engine all the time. Thank you

I don't know if he still has the kits available, but, my local ACE hardware has all kinds of Nylon washers, tubing and shims for sale. Just a thought.

77 AMG said:

I don't know if he still has the kits available, but, my local ACE hardware has all kinds of Nylon washers, tubing and shims for sale. Just a thought.

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Ok thanks, good idea. I was hoping somebody would at least have installed one of them so I could get a look. I guess the bolts would have to be switched with slightly smaller diameter bolts to make everything fit, but shouldn't be too big of a problem.