Door panel vapor barriers?

[got2haul]

I'm going to install new door panels this weekend.  When I removed the originals, there was no plastic vapor barrier covering the openings inside the door like you see on modern vehicles.  Is that a recent technology, or did our trucks originally come with those?  Mine is the Custom Deluxe trim level; maybe the barriers were installed on upper trim levels?

There was a ton of dirt caked on the inside of the door.  Does a vapor barrier prevent this sort of thing from happening?  What would I use to make a vapor barrier?

[Captkaos]

From what I understand, all of them had it, but I am sure by now the barrier is LONG gone.  Early trucks had a paper type barrier, the later model ones had a formed plastic barrier.  You could use and clean plastic to cover it though.

[got2haul]

Is a vapor barrier necessary?  When I removed the panels, there was a ton of dirt caked onto the metal under the panel.  I presume it was because it either never had a barrier or the barrier was removed early on for some reason.  I see no evidence of one (small bits of torn paper or plastic).

[Captkaos]

the older trucks had the paper held on with some Tar-like substance.  Is it necessary, no.  But it will keep dirt/dust from blowing around behind the door panels.

[Fordeatinz71]

my '79 Custom Deluxe had it.  it just normally gets removed when the doors are worked on...

[xtremjeepn]

Not sure what the barrier would really do with the big vents in the doors. (bottom and side).


FWIW I recently had the doors apart on my 2 Audis and neither one have vapor barriers.

[Dragon]

The idea behind the Vapor barriers behind door panels, was to help keep dust/particle debris & moisture to a minimum, for both at the back of the panel, and from reaching the interior....   Original Door Panels were also made of a Wood/Paper/Cardboard Media, that was covered in Fabric/Vinyls, and with the barriers in place, they would be the ones exposed to the elements instead of the panels...

Later panels became a combination of Fabric/Vinyl Covered Cardboard uppers, and ABS Plastic Lowers, with the Paper Vapor Barriers being replaced with a longer lasting sheet of plastic (Also to help protect any electrical switches)...

Most cases whenever a door is Repaired/Serviced, the first thing to disappear is the Vapor Barrier, as generally they are ripped or torn while accessing the inner-door...

As for how the barriers work in conjunction with the vents in the doors, usually there is a cut-out or flap in the barrier to allow the vent to work properly....