I got a “thingamajig” on my truck that I have never seen on a vehicle before. I am sure its been discussed in one of the forums but I can’t search for something I don’t know what to call. It’s on the rear of the left-rear spring mount. It’s a large metal disk affixed by its center by what appear to be rubber mounts. It’s free to wiggle but not to rotate. I can find no wires or sensors connected to it. Can anyone give it a name and purpose?

2005 F150 Work Truck
6cyl Man. trans.

 

i would have to see a pic

 

 

I'm pretty sure thats the vibration dampner that some of the 150's have installed now to cure the bed shake wyouger. Thats the first one I've seen but it looks exactly how they've been described in the 04-05 forums.