Just finished the front doors and speaker pods, but when i got to the rear doors there was a protective film (see pic), should i deaden over it or take it off and deaden over moving parts?

 

I would take it off and put it back on after if it still fits.

 

well do you know what it is? do you know if i even need it on there at all?

also, do you think deadening the whole car is worth it? will it make a big difference from just the doors being deadened?

 

Do not deaden over it. The purpose of deadening is to lower the resonant frequency of the metal so it doesnt make any noise when it vibrates.

 

Really ?

I though it was to reflect the audio and keep it in the car...so does that mean i should deaden inside the doors as well?

 

if you have extras, yes. The sound always stays in the car. The deadener reduces road noise which makes it appear that your sound is louder and clearer. In my doors I have 3 layers of deadener and 1 layer of 1.5" thick sound absorbing foam. Then again, I also have 10" subs in the doors.

 

Ya just make sure you put it on to the steel itself. IF the deadener falls off its not doing you any good. Clean the surface really good, even rough it up with 40 grit sandpaper if you want, this will help it adhere better which is the key. That plastic sheet is just a vapor barrier that is it. By sealing up the holes in the door with deadener it will now become your vapor barrier, no need to reinstall the plastic.