What the hell is this tube hanging from the transfer case?

[Gilgamesh]

There is a strange tube dangling from the transfer case of my 2000 Eddie Baur 4x4 Ford Expedition.
The soft tube is clamped off on one end, and the other end connects to the transfer case.

There is no leakage, and the vehicle drives fine, but I suspect someone was stealing transmission fluid.

I do not know where the other end of this tube is supposed to connect to.

So what the hell is this tube?

 

[toms89]

If its coming off the front of the transfer case near the tranny it may be just the vent line. It should be a barbed end with a cap but someone may have added a hose to it.

 

[Maverick1701]

If its coming off the front of the transfer case near the tranny it may be just the vent line. It should be a barbed end with a cap but someone may have added a hose to it.

this is my guess as well