I just got my new G35 Coupe and the road noise is kinda loud, and from what I hear it is because of the big 18 inch tires.

And I was thinking that we could dramatically reduce this noise if we sprayed some undercoating in the wheelwells as a can of the stuff is only $5-6 I think.

Anyone think this is a good idea? Post here as this could help alot of people out.

Thanks.

Jason

 

Bad idea. How will you get to your light bulbs? Undercoating is messy and I can't tell the diff after one's been done.

Many have had success with dynamat. Do the trunk and in the doors and floor panels. Should help alot.

2004.5 Coupe/5AT/Ivory/Everything but chin spoiler/Z Tube-Popcharger/Crawford V5 Plenum on the way

 

Where do I go to find out more info about Dynamat, and how hard is it to install the stuff in the doors, as I don't really want to take them apart. I assume putting it in the floors is much easier as I would just stick it underneath the carper right?

Thanks again.

Jason

 

http://www.dynamat.com/

Your local audio shop can do install if you don't want to. If you want it done right, you'll need to remove panels which is no big deal.....go to DIY section here and lots of instructions with pictures.

2004.5 Coupe/5AT/Ivory/Everything but chin spoiler/Z Tube-Popcharger/Crawford V5 Plenum on the way

 

you can check out www.b-quiet.com/ too.

2 G or NOT 2 G, there is no question!

 

I used materials from b-quiet.com (on flat surfaces, interior) and quietcoat.com on uneven surfaces (underbody, wheel wells). After 6-8 hours on my driveway I was able to reduce road and engine noise from radio-level-14 to radio-level-10 (at 3k rpm on a highway). It's easier with a friendly garage. Notice that for wheel wells, you get better effect if you remove inner plastic covers and stick "browsn bread" directly to the body. QuietCoat can be painted over and is not sticky after drying.

 

What about basic 3M brand Undercoating in a can for the wheelwells instead of the stuff from Quietcoat.com as it is much cheaper? And I hear that Dynamat Extreme is much better than the stuff at B-Quiet.com. Is this true? I mainly want to minimize road noise around the wheel wells, doors, and the floors.

Also, how do you install the sound-deadening material underneath the floors? Do I just stick it underneath my carpets or do I have to pull up the whole floors?

Thanks again for all your help.

Jason

 

Jason,
The primary purpose of undercoating is to protect metal body from mechanical destruction (sand, gravel) and prevent later rust. Manufacturers add some deadening material but this will not be as effective as the one designed for deadening purpose. You can always apply undercoating later. Concerning carpets - I removed (very carefully) plastic trims at the edge of carpet and placed b-quiet material underneath (you will be surprized what's unde the carpet). Just try not to break the clips.
Jerry

 

Do you have any pics of your carpet removal job, as I would not want to break any clips as well? I bet it is just cardboard underneath the carpets, am I right? As I know they sometimes use it in other cars.

Thx again.

Jason

 

I will take some pictures on Saturday and post them...

Jerry

 

Jason,
Here are some pictures I've taken while preparing to put sound insulation under the carpet. I hope they don't need much explanation. 1- remove plastic trim along the door frame (start from rear), use flat screwdriver, pull up, do not use too much force, 2 - remove plastic cover of fuse box, 3. pull up carpet from around white plastic mounting, 4 - place your insulation under carpet.
Jerry



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More pictures



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Continued...



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Carpet....



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Under the carpet...



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