Transfer Case Vacuum Lines?

[jarhead3531]

1997 1500 4X4. Had to replace transmission and helper pulled lines off of transfer case. The 4 in the "plug" are a no brainer as far as where they go but the "big one" is the one I am not sure about. Does it just vent to the outside or does it connect to something?

 

[16 Bighorn 4x4]

If you're referring to the vent hose, it just gets connected to the transfer case vent tube nipple and it's attached to the firewall and should have a one-way cap on the end of the hose.