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Hello all, so I have a CLS (diesel - petrol to expensive in Ireland ) am not happy with the tyre roar from the back over certain road surfaces. Done ALOT of research and took the plunge on Dynamat. There are alternatives that are cheaper but not as effective and ones that are the same price but heavier to do the same job.
2 things I have learned. 1 dynamat (or any dampening) is the first in a 3 step process - step two is closed cell foam and step three is mass loaded vinyl. 2 Dynamat does not require 100% coverage, so dont waste your money and time by over applying you are simply weighing the car down and using more material than required (note you do need 100% coverage on the closed cell foam and the mass loaded vinyl). 40% coverage across 70% of the pannel with a focus on the centre is the rule for dynamat. I emailed dynamat and the place I bought it from. Both confirmed this (did recommend 100% cover over rear wheel arches).
Started today and done the bonnet/hood. Problem was it is a double skinned bonnet. I am not sure but I dont think there is any merit is applying it to the inner skin so I applied it through all the holes so it is in direct contact with the outer skin. I did apply in the centre inner skin just in case. No difference in stationary decible before and after.
Plan on doing the boot/trunk, wheel arches, rear seat and doors (they also have a shield so can't access outer without removing rivets). I have readings at several speeds so will check decible count on the move when everything is completed.
Before Clips where difficult to remove, had to just rip them put with a plyers, all went back in though Dynamat in all the holes so it is in contact with the outside skin of the double skinned bonnet/hood
You don't show the rear of your car, so I cannot see if my "fix" would help you.
I have a W212 E400 4Matic sedan. My previous car was a Lexus LS430 which, even after 150,000 miles, was nearly silent. The E-Class, with its Sport Suspension, was far from quiet. Mine sounded like I was driving with a back window open. I had a LOT of road and tire noise evident in the rear of the passenger compartment.
I tried a trick I had used on other cars. I opened the trunk and removed the spare tire and everything else that is stored in the tire well under the trunk floor. I then lined the floor with common fiberglass wall insulation - the sort that is sold in rolls at home centers or hardware stores for insulating between the studs of walls. I put the spare wheel back in over the insulation, then placed another layer of insulation over the tire, covering the entire area. I then just closed the trunk floor over all the insulation.
When I took the car back out on the road, the difference was amazing! Almost all of my tire noise was/is gone. This was because the tire well in my trunk is merely a large plastic tub bonded to a hole in the trunk floor. The car comes with NO insulation in that area, so road and tire noise flowed freely into my car. About $15 USD of insulation and the car sounds like a luxury car, as it should. Too bad the factory couldn't do this for us. . .
My previous 2 cars were Lexus also (IS 200 sport and 220 Sport) much quieter and much better sound systems (I had Mark Levinson - my biggest regret is not ensuring the Merc had Harmon Kardon - my next project ).
Yes step 2 will be the rear of the car, it might be a few weeks before I get around to it. But plan is partial Dynamat cover and closed cell foam and mass loaded vinyl.
It is no where near as expensive as the Dynamat (a company called Dodo do it in England and shipping is not to expensive.
Trunk/boot and rear seat the main plan, cost about €100. As I am only doing partial Dynamat coverage I will sell the excess so hoping will cost me around 50!
Did you use fibre glass insulation - as in the yellow fluff with tin foil? I would not be happy breathing that in? The place I got my dampning from does sell an insulation but it is made from recycled plastic bottles so it not an irritant - Google dodo thermo fleece.
It does say it can be used as sound nsulation, might be easier to cover the floor in than the other two. Am going to have to check out weight vs performance! Is definitely thicker so wouldn't work under the seat or between the rear firewall but maybe for the boot/trunk - 2 layers under the tyre and above as you suggested. Will have to research and have a think about it!!!
I recently changed over from the ContiProContact tires to the ContiExtremeContact's and I've got a lot more road noise. Almost to the point i think something might be wrong. My noise is coming from the front though. I'm def going to try this insulation in rear tire well but I hope I find some solution to the front.
Different tyres have different decible ratings, something I had never worried about but will be taking into consideration for future tyre purchases.
I had a look under the carpet in the front foot well. Has very thick foam where you would rest your feet so seems to be fairly well insulated. I didnt remove any trim to see further.
I dont know anything about it but worth researching something like the below:
Danoely - Yes, I did use that pink stuff that they sell at the home centers. I didn't worry too much, as I rarely breathe the air from the spare tire well in my trunk .
TechSuperstar - I just did the opposite. I changed from the stock ContiProContact tires to the DWS06 ExtremeContact tires, and my new tires are a lot quieter than my old ones were. The one thing we all need to remember when comparing new to old tires is that old, worn tires are usually a lot noisier than they were when they were new. The get loud very gradually, then when we get new ones, we think we have miracle tires. I guess the only way is to compare new tires to new tires, which most of us just can't do. If your noise seems to come from the front, especially in a W212 E-Class, I would look into wheel bearings and suspension parts, too. I had far more noise from the rear than front.
Sold - 2012 CLS550 OE Stage 1, Res delete, chrome delete, 20" rims, more to come
SteveE400 - Do you have any images of your install? Not trying to highjack Danoely post, but would be interested in seeing where you applied the insulation. My CLS550 seems to have a lot of road noise coming from the rear of the car.
Factory sound proofing and dampning, note thick foam over wheel arch Note factory dampnening under "fluffy" insulation Same on orher side Factory other side Peeled back foam and dampning fell off at the slightest touch so was not doing the job of dampning as not solidly connected to the pannel Dampning after it fell off Dynamat applied, some factory left (done other sode forgot to take photo) also was able to push my hand in behind the foam to apply where i couldnt see (plenty of room) Foam put back all you cam see is the dynamat at the bottom Rear seat from the boot/trunk Dynamat apllied Note of caution ot is difficult to get the factory liner back into the corners THE CULPRIT, i believe this to be where 90% of the noise is coming from. The 'nock' test reveals this to be the most resonant pannel. Nice big hole to the outsode world Dhnamat applied, only where the nock test revealed resonance Also done the boot/trunk
I plan on applying mass loaded vinyl and closed cell foam over the above. Will revert with decible levels before and after when complete (just an app off my phone)
I see loads of people complaining about their HK system, unfortunately I don't even have that! I have the base factory system. It is acceptable at low speed but awful on motorway or if sunroof is open (even on tilt). No centre speaker in dash, no subwoofer in rear. Just have the tweeters in the door and the 4 speakers (1 in each door). I can't find any info on line regarding power and my merc deale can't tell me. I am considering getting a pair of HK tweeters as a starting point. Am told door speakers will make minimal difference as there is not enough room for speakers to perform and the best bang for my buck is to get an active subwoofer to take pressure off the factory speakers. So the Dynamat is not really needed for speaker resonance in this case, although I am considering putting some around them to see will it help performance. Main plan for dynamat is step 1of 3 to reduce tyre roar (step 2 closed cell foam and 3 mass loaded vinyl) so that my crappy factory system can be heard at speed without having to blast it. I miss my Mark Levinson from the lexus that was awesome, I remember the door mirrors used to bounce with it
Factory dampening and thick foam rear seat from floor to seat, so no need to do anything Rear seat bear metal under the factort grey fluffy foam Applied dynamat on bottkm of rear seat (including under centre console) Also on the back of the plastic pieces
I think a lot of people opt for the Dynamat-type butyl backed adhesive as soundproofing. Some even go as far as using that asphalt stuff which gives off an odor. I tried the butyl backed stuff in the trunk, but I wasn't that impressed. For anyone that is looking to have true sound deadening the do what I did: ditch the butyl backed stuffed, its not even that great. I opted for rebounded foam. It's cheap and you can probably do your entire car with one roll (I think it's like 25 sq ft or something. It's pretty much the size of a large area rug). In my opinion this is 100% better than any butyl backed product that people are using now. As you can see from the photo, there is zero issues with forming it over the contours of the car. I'm using a spray adhesive to apply it. The floor is done already, and I also re-did my carpet as well, I opted to use plain black wool felt. I am in the process of doing the entire car: (doors, trunk, firewall, hood, wheel wells, etc.) It sounds like a lot of work, but it's pretty simple. So far with just the flooring done, I have noticed a huge reduction in road noise. Driving over cracked roads with small potholes, the sound is only muffled thumps as opposed to clanking metal or rattling from rocks hitting the exhaust pipe or metal heat shield under the car. I also, attached a layer of it to the backs of the metal heat shields and then covered that felt. HUGE difference. And yes, I tested the durability of it with a heat gun set to 1580°F for 2 mins continuous and it only shrank a bit, but remained intact and didn't burn or melt. Rebounded foam. Entire w201 floor will be covered.
05-11-2019, 05:30 PM
) am not happy with the tyre roar from the back over certain road surfaces. Done ALOT of research and took the plunge on Dynamat. There are alternatives that are cheaper but not as effective and ones that are the same price but heavier to do the same job.
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