I have a 2000 F150 XLT supercab 5.4 4x4. Anyway, there is a rattle coming from the passenger side that has been driving me crazy. Before anyone suggests something mechanical, let me tell you I KNOW its interior.
It has been happening now for probably around 2 years. When I go over a bump, sometimes, not all the time, there is a rattle from the passenger side. It sounds like plastic is rubbing plastic, or like something is loose and bouncing around. I read about a trick getting velcro tape and putting the soft side of the velcro tape so it is in between two rubbing joints. That supposedly quiets any rattles or noise. I did that on the glove box pads, under the selt belt tensioner, and where the seat belt rubs the plastic. Better, not gone. A few days ago I discovered the plastic shroud on the side of the passenger seat (around the recliner lever) was loose, and rattling against the metal bracket. I took it off, applied the velcro tape to the rubbing spots and tightened it back on. Again, better, not gone. I am now directing my attention at the passenger door itself because the plastic interior panel seems to have a lot of free motion when you touch it. Maybe that is rattling? Is there a trick to solve that?
Also, does anyone else have any ideas or experience as to what this might be exactly?
Looks like you found the culprit - and as Almighty suggests, it has to be one or more of those clips are broken off the panel - and now it's free to drive you crazy. When you remove the panel, which is now probably being held on by the handle screw, you might find those clips in the bottom of the door shell. If you can retrieve them, then good plastic cement, AND an additional piece of plastic (I melted the end of a plastic knife onto the repair with an old soldering iron) will keep it in place.
1998 SuperCab Lariat, K&N CAI, LED Halo headlights, LED gauge / temp / headlight switch panel mods
Pop the vertical piece off on the right side and there's a screw near the bottom there. Then the oval piece around the door handle and there's a screw behind that, pop up the piece with all the switches on it and undo to harnesses. Then lift the panel straight up and off and undo the light from the backside. Now your door panel is off, it takes me about a minute to take it off