DIY - Reduce Rear Hatch Audio (Sub Woofer-Generated) Vibrations
 

Some recent posts on the NX's sound system and speaker upgrades got me thinking about how to reduce the unpleasant car vibrations generated by the sub in the rear hatch, at a minimal cost and effort. This is in addition to buttoning down the license plate and placing rubber or felt as a common fix posted in many forums and threads.

I used two 454g cans of med-high expansion polyurethane foam (i.e Great Stuff, Mono, etc.) to fill about 2/3rds of the door cavity while avoiding the door latch mechanism, the rear camera module, and the sub.

I used fabric tape (hockey tape) along the hatch's interior trim to minimize plastic-on-plastic or plastic-on-metal vibrations.

Result - with volume cranked, significantly reduced rear exterior vibrations. As well, no interior vibrations at rear and to my ears, a "cleaner" slightly louder and deeper bass. :thumbup:

My usual common sense disclaimer that I nor CL is responsible for any damage incurred in doing this DIY. With this out of the way, see video below and hope this helps.

Posting to do this weekend.

Great, post your results!

Corrado - you think I can get the same or better results with sound damping sheets like dynamat?

^^^ +1.

The thing is, the plastic panel is clipped on with many clips (at least 20) from my recollection (seen through the hole when you remove the plastic bottom covers) and if one's willing to replace some of those clips which will likely get damaged, the panel can be removed. But, to get into the metal door cavity, the only large enough hole is from the sub making it a difficult install for a Dynamat across the entire cavity door, IMO.

maaan, I'm all thumbs. I was asking but I'm going to take it to a pro when I'm ready. lol

I tend to agree.

Amazon prime is being slow, and my foam will arrive Monday. Hope it helps.

@Pinhead, that is my same concern. What if you need access in there sometime? Especially on a lease, I wouldn't want to do anything permanent.

Now that the colder weather is here in Canada, the rattling is definitely getting worse. I'm finding the loudest rattling in the mornings and quieter by the time I get to the office after driving for 30 mins after the vehicle has warmed up inside.

Finally got around to spraying the foam in, and it seems to have made a huge difference thus far, with no adverse effects. Thanks corrado!

Great to hear and validate the fix! :thumbup:

For those not wanting to use the foam, which is honestly a terrible idea to begin with, you can always buy denim insulation or fiberglass insulation and stuff it into the cavity. This will achieve the same filling effect without introducing the mess of Great Stuff. It's significantly easier to control and it can be taken out as desired. It will also have better sound absorption properties compared to Great Stuff. The easiest way to use it would be to remove the panel and lay it in sheets, but making an access hole and shoving it in will also work if you feel nervous about removing the panel. It'll just be more work.

The reason I say the foam is terrible is because it's a semi-permanent "fix" that makes a gigantic mess, and because it relies on air to solidify, it takes a long time for it to fully harden when used in large quantities. This is why two-part foams are typically used for cavities, again a semi-permanent fix, because it's a chemical reaction that won't leave certain parts unhardened like Great Stuff will. And, as someone stated, a dealership might very well use it as grounds for not covering a warranty or charging you out-of-pocket fees for creating additional, unnecessary work for them.