I lifted the left rear seat on a 2006 f150 FX$ and there is this black box bolted to the seat. it is about 18inx3 foot maybe. im just curious if it opens? Also does the rear of the seat flip down? Here is a pic.

 

That would be the factory subwoofer for the upgraded/premium sound system

 

Thanks man! Do you know if the back of the seat flips down?

 

The back opf the rear seat does not flip down in these trucks easily. I believe it can be unlatched to do so but its not meant to do on a regular basis.

 

Technically, the rear seat does not flip down at all. As Drew said it can be removed, but it's not a task you'd want to do on a regular basis.

BatteriesNotINCL has a good video on how to remove the rear seat if you care to do so. Here's a link to his thread:
https://www.ford-trucks.com/forums/8...rear-seat.html

 

Ok thanks for the help guys!!! I just got this truck i went from a 06 350 to a 06 150 so im still getting used to this truck lol

 

That's a pretty big change but I think you will be happy with the 150 once you have adjusted to the differences. Both Chandler and myself have 2006 Fx4 models and have had little to no issues with them other then routine stuff.

 

I have an 04 FX4 and that box is a factory sub woofer for your stereo system. My seats only fold upwards and not forwards. Hope this helps.