I'm betting it's a hydraulic hose. I think there's 4 in there. I would replace them all. I had one go out and then another before we even finished the year. Seems like they degrade over time and when one goes, they all need to be replaced. I just went to the local JD dealer and they made the hoses for me. The ends were not quite as compact, but they worked. I think you can just look up under the cab and see the other end of the hoses. Ours dripped on the feederhouse when they leaked.