What is this part & why does it look broken?

So while setting up the wiring for my Explorer (98' V8 EB Edition) I noticed some thing that looks like a shock just above my rear diff and it appears to be broken or almost broken. However I have no idea what it is or what its function is, any ideas?
http://img374.imageshack.us/img374/2156/1001124aq6.jpg

I have a 98 Mounty and a 98 Sport and I have never seen that before. What does the other end hook to?

That is the mysterious 5th shock-

edit
no it isn't

Jt....the picture doesn't look like what I've seen as the fifth shock. It looks like something to do with the ARC ride control.

Not sure that is the 5th shock -- the 5th shock goes from the side of the diff and forward to the frame rail (not back like in the pic).

Bingo Jesse, that is the rear height sensor for the ARC suspension. There are two mounting points at the top and bottom for the two links. That height sensor looks like a shock with the boot on it.

Your sensor has come off from the visible mounting stud above. Try to save those parts, that linkage assembly is about $200 from Ford. Regards,

well there you have it

Sorry for the misleading info.

I need some of Iz's lemonade I think.

Or you've had too much lemonade -- its making you go wacko!

Geez,
what do you put in this stuff

Sweet, I was scratching my head trying to figure it out. Thanks again.


David

Thats just come off the ball stud above it, its black in your picture, make sure to grease it b4 you put it back, then you can release the bottom ball joint and grease that one and the plastic ladder thing in front also has the same ball joints so do them also.