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Discussion Starter #1
my car has a terrible rattle from the rear. i can't tell if it's from the rear shelf area/speakers or the decklid itself. has anyone else experienced this? any suggestions for getting rid of it?
 

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it's the rear shelf.
 

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Mine is the same. Along with the door seals and one of my dash's wood pieces, the noises are driving me insane. As a result, I listen to the iPod too loudly these days and am probably going deaf.

WHAT? HUH? :cheers:
 

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I've been having the same problem, only mine goes away after about 5 minutes. They replaced the passenger rear speaker cover and it keeps happening. No clue why it takes a while to quiet down.
 

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As Jayson states, it is probably the rear shelf. I had one of my kids go back there and start pressing things to get the rattle to stop. Once the rattle was pinpointed, I stuffed a piece of tissue paper between the rear shelf and the rear glass...the noise went away.

The next time I was at the dealer's they fixed it, but I doubt they would have if I hadn't done all of the above!
 

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KevinM said:
As Jayson states, it is probably the rear shelf. I had one of my kids go back there and start pressing things to get the rattle to stop. Once the rattle was pinpointed, I stuffed a piece of tissue paper between the rear shelf and the rear glass...the noise went away.
That's it, but exactly what, who knows. It seems to be the brake light assembly hitting the shelf. The black brake light bulb cover in the trunk next to the sub is the worse culprit.
 

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a_ok2me said:
That's it, but exactly what, who knows. It seems to be the brake light assembly hitting the shelf. The black brake light bulb cover in the trunk next to the sub is the worse culprit.
Since the subs and speakers are both in the rear deck, it's likely some of everything vibrating...Pin pointing it then is tough, since it's unlikely its one little thing...You could rip up the cover and dynamat the metel on the deck and replace that may help but i can't say for sure, it would keep the metal at least from vibrating and illiminate that from concern and the added thickness would maybe keep the deck cover from moving around....maybe, it's an idea thats sound in theroy at least
 

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Dynamat is only part of the solution. The woofers are pushing or at least "trying" to push air through the rear deck shelf, which happens to be sealed, in the sense that the volume of air attemting to pass through the rear deck shelf is trapped or sandwiched between the woofer itself and the bottom portion of the rear deck shelf, thus the insense rattle at high volume. Solution, you'd have to have your expert stereo shop cut the rear deck shelf directly above the woofers and create an opening, similar to large speaker grills. This along with the Dynamat will totally eliminate the rattle of the low end bass. This is what my expert stereo shop did, and it works. Last, if done properly one can't even detect that the rear deck shelf has been cut, depending on the shape of the cut/contour. It actually looks as if it an OEM grill for the rear deck.
Robert :viking:
 

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FAST 5 said:
Dynamat is only part of the solution. The woofers are pushing or at least "trying" to push air through the rear deck shelf, which happens to be sealed, in the sense that the volume of air attemting to pass through the rear deck shelf is trapped or sandwiched between the woofer itself and the bottom portion of the rear deck shelf, thus the insense rattle at high volume. Solution, you'd have to have your expert stereo shop cut the rear deck shelf directly above the woofers and create an opening, similar to large speaker grills. This along with the Dynamat will totally eliminate the rattle of the low end bass. This is what my expert stereo shop did, and it works. Last, if done properly one can't even detect that the rear deck shelf has been cut, depending on the shape of the cut/contour. It actually looks as if it an OEM grill for the rear deck.
Robert :viking:
Acually sound waves move through things pretty easy, and are not trapped, I'm glad it worked though.
 

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I took one of those brown felt cupboard door buttons (the ones with a sticky side) and pulled the black light cover, stuck it to to the inside of the cover and VOILA my little rattle was gone. (I also did the same thing to my license plate cover, whenever the tag frame was thumped a little by bass, it rattled against the plate)

I use these little felt buttons a lot.
 

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I no longer have an M5, but the noise in mine went away when I raised the rear electric window shade.
 

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Jayson said:
Acually sound waves move through things pretty easy, and are not trapped, I'm glad it worked though.
It's not the sound waves he is talking about. He is talking about the "air" the woofers are trying to displace.

And sound waves do have touble moving through things, it just depends on the material and thickness of that material. Some frequencies may pass and others may be dampened or attenuated. Sound is reflected more as the frequency rises. Lower frequencies tend to pass through but in reality it is the impact of these low frequencies hiting the surface. That is what is being heard. The first order reflection and the resonance of the material with some of the original wave as well.

Jordan
 

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You do know a sound wave is nothing more than a ripple in the air, at it's most basic. And just like you said, lower frequencys pass through things very easy, the little cardboard peice that covers the rear deck is not gonna make it hard for sound waves to pass.
 

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Jayson said:
You do know a sound wave is nothing more than a ripple in the air, at it's most basic. And just like you said, lower frequencys pass through things very easy, the little cardboard peice that covers the rear deck is not gonna make it hard for sound waves to pass.
Yes, I agree with you. But he stated the air was creating it. No matter how thin air is it still has a density and when something is trying to pass through it that also has a density the less dense substance is going to give way.

Low frequencies do create force and that force against an object will have an effect on the object as well as the air. Quantity or volume also plays a big part in it. The higher the volume the harder it becomes to displace the air in a specific cavity. If the air can not be displaced at the same volume of the wave something else is going to give i.e. the parcel shelf.

Jordan
 

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I just recently took apart the rear deck of my car for a sub upgrade and found that the rear brake light was completely loose. Along with the bolts that hold the rear sun shade in place. The bass from the stock system had loosened all the bolts that kept everything tight. I built a new rear baffle, installed new subs and used lock tight on the bolts to keep them from moving again.

Also the rear shelf itself rattles just from the air movement of the bass. Dynamat will solve that problem.
 

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I finally found the second rattle on the shelf. Again, the first was the brake light cover shaking loosely that was fixed by applying a coat of silicone around the cover. The second is related to the horizontal sunshade bar rattling against the shelf when it's down. I noticed that if I raise the sunshade, the rattling goes away because the horizontal bar no longer rubs the shelf.

Does anyone have a suggestion on how to resolve this? I might apply a coat of silicone on the bar.
 

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a_ok2me said:
I finally found the second rattle on the shelf. Again, the first was the brake light cover shaking loosely that was fixed by applying a coat of silicone around the cover. The second is related to the horizontal sunshade bar rattling against the shelf when it's down. I noticed that if I raise the sunshade, the rattling goes away because the horizontal bar no longer rubs the shelf.

Does anyone have a suggestion on how to resolve this? I might apply a coat of silicone on the bar.
By the way, I didn't see Chuckc's sunshade response. I didn't want to mess with silicone so I used 2 layers of black electrical tape along the sunshade. It worked. 3 might work better. Then for the second rattle, it was the driver side speaker grill. I stuck a piece of clear 3/4" vinyl bumper between the windshield and the rear shelf and it worked. Applying some electrical tape directly to the locking clips or the edges along the speaker grill might work better, but I didn't have a screwdriver at the time to remove the grill.
 

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I found another rattle and it’s the biggest culprit of them all. There is a piece of material that I think is foam and it is in between the metal part of the frame and the interior rear deck shelf. It is molded to the shape of the rear deck. The backing of that material seems to be a hard rubber or plastic. It vibrates against the metal and causes a very annoying rattle. I solved the problem by using a trunk liner material between the metal of the rear deck and the plastic/hard rubber lining of the foam pad and the rattle went away. Keep in mind that I had already fixed the rear sun shade and the brake light rattles.

Hope it helps.
 

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Discussion Starter #19
Whiteyford said:
I found another rattle and it’s the biggest culprit of them all. There is a piece of material that I think is foam and it is in between the metal part of the frame and the interior rear deck shelf. It is molded to the shape of the rear deck. The backing of that material seems to be a hard rubber or plastic. It vibrates against the metal and causes a very annoying rattle. I solved the problem by using a trunk liner material between the metal of the rear deck and the plastic/hard rubber lining of the foam pad and the rattle went away. Keep in mind that I had already fixed the rear sun shade and the brake light rattles.

Hope it helps.
thanks...will be doing all of these this week.
 

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Sometimes I find my sunroof rattles as well. I just wiggle it a bit and then it stops. It is not the actually glass part but the headlining cover part.

- Kin
 
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