What does this thing do?

[kenr74]

I had my 1994 X into the shop yesterday to get some new 4.10's put in. It's a huge improvement with the 33's. When I got there to pick it up they had three guys searching for a part they couldn't find. I wish I had a picture of it but they still haven't been able to find the damn thing. They are trying to track one down through Ford to replace it but they didn't know what it was for either.

I hope this makes sense but I really have no idea how to describe it. I think it has something to do with the ABS. It on the front end. If you take the brakes and caliper off you can see it. It slides into a hole and then a screw holds it in place. I'm driving the truck fine without it but I'm wondering what the heck it is and what it's for.

 

[Alec]

It's an ABS sensor most likely. Your ABS or Brake light should be on. Without it, you don't have ABS.

 

[kenr74]

I was expecting the ABS light to come on but it hasn't. I haven't tried locking them up but the light does work because it has come on in the past. This thing is just a piece of metal that doesn't seem to be doing anything. It doesn't attach to any wires at all. It just looks like it plugs a hole.

 

[Alec]

In that case your truck only has rear ABS and it is a plug like you said.