Identify this exhaust pipe

Can someone identify the purpose of this exhaust pipe. I have a maxxforce engine. Trying to figure out the steam, its a new development although i have been losing a lot of coolant for the past 3 months, might be related. Any input is appreciated.

Here is video

 

Great.....

Might be time to get a pre 2000 truck anyways. Gonna be sad to see this one go, this prostar sure is comfy.

 

Ill have to post a picture here in the morning when I have daylight , looks black to me but im colorblind, i dont trust my color identification

 

I couldnt wait went out and checked. Somthing is not right. Its almost as if its clotting.

 

Im thinking so also. Ive lost a gallon of coolant every 100 miles I drive for the past 3 months. Cant find a leak neither can mechanics. Going to get the oil changed. I need need to cross my fingers and keep it running 2 more weeks.

Runs smooth when its running thats all i can say positive. The problems with them we have had is too long to post. I love the prostar though, the turning on them is so helpful for the work I do.