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Are The Factory Car Door Moisture Barriers Needed?

24K views 11 replies 5 participants last post by  Ixionic  
#1 ·
I have a 2001 Eclipse GS i recently bought 2 months ago and while replacing all the speakers (that the previous owner did a shitty job replacing) i noticed both doors were missing the factory moisture barrier.

So my question is what will happen if i dont replace those moisture barriers? Some cars seem to have big problems with water leaking into the car when the moisture barrier is torn/removed, but i havent noticed any water in the car after a car wash so should i be fine without one?

I decided to leave the door speakers out for now cuz im afraid my new speakers will get messed up from water seeping into the doors. Is that even likely to happen or am i just being paranoid? I was also thinking of dynamatting the doors so would that work just as well? Thanks again for any and all help! :)
 
#2 ·
If the speaker cones are paper, you might have an issue, but most car stereo manufacturers use polypropylene nowadays so you should be good. If you're really paranoid about it, just buy some 4-mil plastic and reinstall it.
 
#7 · (Edited)
^^^that and you may end up getting drafts coming in past the door panel wherever there are little gaps (switch panel, door handle etc). This can be particularly annoying in cold weather, especially driving at highway speeds.
so where does the air/moisture enter the car from? those big access holes in the door right? so what if i just covered those holes with some plastic tarp? Or do i have to do the whole door?

i'm asking cuz i was planning on eventually dynamatting the doors but dont want to spend that much right now (even for its cheaper equivalents) so i was already planning on covering the access holes but wonder if that would be enough to seal it from the air/moisture?

also its a concern since i was thinking of mounting the crossovers in the door, since thats what i see the most of nowadays.
 
#8 ·
The air and moisture can come in from any number of places such as the wiring boot, drain holes, vents and the belt molding (strip at the bottom of the window).

Just get a some heavy weight poly from Home depot or similar and Duct Tape (must be waterproof), then cut and fit it to the panel, fasten it down securely, and you're done.

I put Dynamat on my doors as well, however it is applied primarily to the outer "skin". What I put in on the inner portion of the door it was fine, and just re-affixed the barrier sheet using the existed goo, or duct tape when done.

It is not usually recommended to put crossovers in the door just from a potential corrosion stand point, but if you're going to, then they MUST be on the inside of the barrier (between the sheet and the door panel)to keep them out of the elements and as dry as possible.
 
#11 ·
Ya thats what i was thinking, and so i think ive decided to try and mount the crossovers inside the car near the kick panels, so this way they dont get messed up by anything related to the door.

Cuz after all the speakers should be good no matter what right? And then a little bit later on i'll seal the inner skin with some dynamat so i dont have to waste any time with a moisture barrier, thank you all! :ndance:
 
#12 ·
If you love Music, Dynamat is the way to go. On my old Eclipse GS before 2005 where it got totaled, I had Dynamat under the carpets, doors, rear seats and I even dynamated the whole trunk. If you have a subwoofer in the trunk, it will hit louder and since there's very little road noise your music just sounds better.

The downside is that Dynamat will add weight to your car. It's heavy when you do the whole car. So you loose a little performance but gain more fun.