my experience with noise- different setup but some lessons I learned.

I did the butyl sound dampener (stinger roadkill) in mine and removed the carpet padding. I put that stuff on the roof sides and floor. It reduced vibration noise and probably blocked some, but overall wasn't worth the trouble in my opinion. I'd do partial install if I did it again, just to add mass to some of the less reinforced areas to reduce vibes.

A year later I decided to reinstall carpet padding and went with rebond padding from lowes and some heavy 3/8" vinyl backed with foam. Since the vinyl was expensive and not very flexible I used it on flat areas mostly. The rebond went under everywhere. This reduced noise to be comparable with my wife's 2014 focus at highway speeds. Jeep is still louder at idle, but I'm fine with it.

My recommendation is to use padding topped with vinyl under the carpet for best combo of cost/effort/results. If I did it again I would go find a heavy 3-8" to 1/4" thick source of vinyl sheet and put that over rebond before putting carpet back in.

The theory as I understand is that the foam creates an air chamber between the body and vinyl and that's what blocks sounds.

Adding mass to the metal body will help, but probably won't get down to noise levels with stock carpet and padding.

I like to think if I tap a dumpster with a hammer it isn't going to be louder or quieter inside whether the dumpster is 1/4 thick or 3/8 inch. It will change the frequency though.

 

We will see. I have the decibel meter... I don't need it to be super quiet.. Just quieter than it was haha. (vibration being the largest issue) its more important to me that I can spray it out with a hose then for it to be as quiet as a new rig (why I ripped the carpet out in the first place). I mean I have no AC and the stroker/3"exhaust is loud already with window down haha.

I have my stock XJ and a couple other cars for a quiet ride I'm just hoping this will quiet it down a bit and mostly stop the vibration.

The stuff has great reviews in the classic car world (lizard skin/hnr/element etc).. who knows! Ill post back.

It dries grey and feels sort of like the inside of Sheetrock haha. Definitely have another coat to do followed by a solid Bedliner coat.

 

Excellent advise and spot on. I also swear by the jute padding under floorcovering.
However, I was presuming that jute was not an option here because it is absorbent and holds water. I think OP prefers an interior that is impervious to water/mud. Rubber mats would be removable. Low-density rubber has trapped air in it, and is usually closed-cell, does not absorb moisture.

 

X2. I personally wouldn't use a roll or spray on coating for the purpose of noise reduction.

Coatings are great for rust prevention, but not noise. After all, to get the most reduction in noise you will want a loose layer of material that can absorb the subtle frequencies. I've found a lot of people whom have used the lizard skin stuff say it's great for lessening heat transfer, but not very good at noise reduction.

Rubber matting placed under the carpet is the best noise reduction material to use in a vehicle (IMO). It's cheap, easy to cut and form, and removable. The adhesive foil backed stuff works but can get expensive quick. A loose sheet of soft rubber provides the best overall amount of NVH reduction.

I've also had great results with this stuff BTW...

http://www.homedepot.com/p/Unbranded...4?N=5yc1vZc612

 

It is irrelevant to my purposes or the purpose of this thread what is the "best" sound deadening material. This is for those of us who have already ripped all our carpet out, bedlined everything and wish for it to be quieter (or those of us who are thinking about it in the future) . Saying "add a mat under/over your carpet" helps no one in this scenario.

I agree completely that there are much better routes for the sole purpose of sound deadening. Having a few buddies who have built competition audio cars, its pretty crazy 1.) how much money it can cost and 2.) how effective some of that stuff is.

*edit* sticking a rubber mat down isn't a terrible idea... But how would that be all that much different from floormats? Anything more than that would be a PITA to remove I would think.

 

I got a little off track there with the padding and carpet bit.

I drove mine around with all interior removed except dash frame, air bags, and the driver seat and it didn't seem any worse than an old utility van. It was way quieter than a HMMWV.

I'd think the micro balloons should hold tiny bits of air. Might help with high freq sounds. It should help a lot with vibrations with he added mass. Throw down some all weather mats and I'd say life is good.

I'd consider a spray in mine if I did it over. The butyl (stinger roadkill, like dynomat) was a lot of work for results that were so-so. Plus, I think the spray liner would deal better with the windshield and firewall leaks that seem so common.

Any idea if the smell is gonna stick around?

 

I have a different outlook on this whole issue. I don't want it quieter. I don't want to dampen vibrations. I have a 15 year old vehicle that is moderately modified and soon to be highly modified. I want to be able to hear and feel everything it's doing, so that I know when something isn't right.

A Cherokee is a driver's vehicle. Unlike a lot of other vehicles, it talks to you if you listen. I really don't want to mute that feedback.

Am I the only one who feels this way?

 

You must be single.

My wife (whom is prone to migraines) doesn't exactly love the drone of mud tires down the highway. It's amazing how much more comfortable a vehicle is when it's quiet, especially on those long trips.

 

The smell from the herculiner goes away in about two weeks lol... Pretty smelly till then. I might try washing it this time after its completely dry to make that faster.


I personally don't mind the noise all that much... All the vehicles that I used in the Army were the same or worse... even my truck at work (just a large box truck) Is pretty loud . The dome light vibrating off my roll bar gets to me though haha. Its more for my 4x4 partner- haha my 3 year old daughter. The vibrations (Windows up) now make her sick to her stomach after an hour or so. Windows down its no problem.

Ill report back tomorrow. It should be dry and on the road again.

 

It's different from floor mats because to do it correctly you need to take the time and cut+form peices to cover the rear wheel tubs, door panels, underneath the seats...ect. IE, all of the places that floor mats do not cover.

 

I got ya. I Just imagine it would be a pain to pull it all out twice a month to spray it out with the hose. Otherwise, what would happen to water that made it in/under it if you didn't pull it out? (Washing with the hose, melting snow off shoes, creek crossing etc) Slowly deteriorate the Bedliner untill it started rusting the floorboards again?

 

I wouldn't put rubber mats down, unless they are removable or completely sealed. My concern is trapped moisture between the rubber and metal body. I'm keeping tabs on this thread. I'm interested!

 

well I got called into work so I cant give you a definitive answer yet but I will say this... I only had time to throw my drivers seat in.. no floor mats and it is considerably quieter. The dome light no longer vibrates against the roll bar and I am optimistic. Its not silent by any means but certainly better. Ill post some numbers tomorrow hopefully!

 

Decibel meter or it didn't happen

 

My carpet is removed, and I tested with an android app called Sound Meter and got 78db going 55mph on the interstate. I'd be interested to know what others are getting. I had my phone on a mount just left of center with the microphone part of my phone facing to the right.