I have 2 L7 12's in a large ported box in my trunk. When putting these in i anticipated a lot of rattling so i dynamatted the entire floor/walls of the trunk (2 layers on the floor for road noise), all around the rear seats up to the bottom of the quarter windows, the deck in the back (where the two rear speakers sit) and both doors. I've had everything installed for about 6 months now and i can't take this rattling anymore. 90% of it is coming from the rear of the car, it sounds like its coming from around the rear speakers, but i cannot pinpoint anything specifially that is causing it. The trunk lid and rear bumper seem to be contributing to it a lot as well, i'd like to dynamat the trunk lid but unless i have some way to cover it up, the shiney dynamat isn't very visually appealing.
Does anyone know of any spots i should really focus on to stop this noise? Im to the point where i don't care if people can hear it rattling outside, as long as it sounds good inside i'll be happy.
Also, does the trunk lid split in two? It looks like it could be two seperate pieces and i could split it and deaden inside where no one could see.

 

use the dynamat then cover that with carpet??i've heard of people using rubber undercoating, then you could paint or get one of those trunk lid organizer. got to be a zillion ways to hide the deadner....be creative.... then post it, i'm gonna do mine soon.

 

yea i was thinking about making a trunk lid cover, but i'm not too creative when it comes to that stuff. The cheapest lid organizer/cover i've seen is on americanmuscle.com, somewhere around $100. i might try to make something out of some thicker cardboard or something first then go from there. any other ideas guys?

 

well i ca hear rattling with my subs too, but my cause is my license plate.

 

what about the vents in the trunk? They can be nothing short of noise makers for large systems. To isolate the noise play something that makes it rattle and then go back and start pushing on stuff to see if it helps it. Push on the rear deck from both sides, lean on the tail lights and licence plate, just work your way around until you have pushed, pulled or pryed on everything you suspect. Once you locate it then figure out if you can tighten some bolts, wedge something under it that will help(some mat or expandable foam). Some rattles are just impossible to get out, just be glad yer not trying to make a neon quiet.....

 

My trunk lid flexed/vibrated quite nicely before i deadened it. I would suspect that takes a lot out.

 

You may also want to check UNDER the trunk area (from under the car) where the fuel lines are. Those are tucked up pretty close to the body of the car (Front of tank/behind axle) You may need to put a pad or something between the lines and the body. I found that to be a point of rattling too.

Found that out when I swapped my exhaust.

 

Hey I have the exact same setup as you. If the noise is coming from your rear deck speakers, you might want to pry off the covers and double check that the screws haven't backed themselves out from the bass. Mine did just that, and after I tightened them it went away.