Nasty black goo coming from the seat backs?
 

I have a 2005 F150 super cab XLT. It has factory cloth seats. I noticed a few spots of "black grease" on the rear carpet. I figured it was from the grand kids shoes so I just cleaned it up. But a few days later I noticed pieces of black foam that had fallen out of the seat back. If you try to pick them up its like black grease, but it is some kind of foam. Both front seats are doing this, I can reach up inside the seat back and find big chunks of this stuff laying in the back of the seat.
What the heck it going on and what can I do about it?
I did a search but didn't find anything like this.

My 06 Lariat with leather seats has the same problem. Chunks of nasty black foam that stains the carpets falling out of the seats.

I too am a recipient of Fords awesome engineering. The stuff is nasty. I would like to know what could be done also.

I know this question is a bit old but thought that I would add what I did to solve the same problem since I couldn't find an answer when I was looking. I have a 06 Lariat with the seatbelts integrated into the seats. Hopefully this helps:

1. Reach under the bottom of the seat back and unclasp the front side from the back side. More than likely a lot of the black stuff is going to fall out and make a mess. Have a shop-vac ready.

2. Carefully roll the leather upwards off of the seat, you will only be able to go 3/4 of the way up but that is all that is needed.
-youtube has videos of do-it-yourself leather replacement if you need a better visual
-This is were I saw the problem, the seat belt retractor has a thin plastic (saran-wrap like) covering. It was caked with the black stuff. That had then grown outwards. I am guessing it is a sort of mildew that was able to grow as moisture from the air condensed on the plastic and was trapped inside the seat. It was definitely not from the seat foam decaying and it didn't appear to be any type of long-term dirt build up. This was identical on both the driver and passenger seats.

3. Remove and dispose of the plastic

4. I used a foaming Resolve-it carpet cleaner, a bucket of warm water, and sponge to scrub the frame, seat foam, and back of the leather covering.

5. Allow to dry thoroughly. I then hit it with a mild bleach mixture and let it fully dry again.

6. Roll leather back over the seat and re-clasp the bottom

No guarantee that the problem doesn't re-occur, I imagine that it helps if you can keep the interior dry/aired out regularly.