front diff hose?
 

ok just recently changed out my stock front control arms in my ZJ. there was a hose that went from the rear top of the front differential on the drivers side that then went up into the engine bay and attached somewhere. it used a clip on the stock lower control arm to stabilize it. When i switched the control arm i just used a zip tie to secure it. well yestureday i noticed it hanging from my diff. I didnt bother to look and see where it went when i was working on it and have no clue where it goes. it looks like it might be some kind of vaccume line or overflow. its a very small diameter hose. please help

Its the breather tube.

Its usually routed up into the engine bay. Just make sure you get it up high, where doesn't matter as much as making sure it doesn't get submerges or damaged by exhaust heat or moving parts.

What if your ds has worn a large hole in it? Somwthing I should replace?

yes i would replace it

There are a couple tangs on the air filter box right beside the P/S pump , the breather tube clips to the tangs and makes a half circle bend so the end of the tube points down.