Take a look on the other forum. TNT Baker is having the same problem in the cold weather, seems to be a condensation issue inside the front cap.
It's an ongoing thread with everyone offering suggestions but the best one so far seems to be drilling a couple of vent/drain holes.
As mentioned, there are no water lines up there.
Vaughan & Tracy 2013 RW 36RL, 2013 F350 DRW CC, 2016 Focus. MorRyde IS, MorRyde pinbox, disc brakes, Comfort Ride Hitch. "Life is to be embraced, Grab it with both arms ! "