I noticed a small diameter hose hanging down from under my truck. I traced the connected end back to the where the transfer case mates with the transmission. I think this may be the transfer case vent hose. Where does the other end connect? I found an open clip with an inside diameter the same as the outside diameter of the hose leading up to the rear of the intake plenum. I am not able to see between the rear of the engine and the fire wall and not able to feel any connectors where the hose could reach.

My truck is a 1998 Dakota Club Cab 4x4 with a 5 speed manual and 5.2 liter engine. The tag on the transfer case says NPG 23D HD but I know it is a part time transfer case which I think is an NV233. The transmission is an NV3500.

 

the breather hose should not be connected to anything. it just needs to be above the highest level of water you plan on driving in. there however, should be a cap on the open end. kinda like on a distibutor cap breather.

 

it might be the vacuum line between the t-case and the engine. that vacuum line would attach to a switch on the top of the t-case, which would switch the vac on the lines to the cad, to engage/disengage the front axle. Dak's have cad's dont they ? i hope so or else i will look stupid.