Atleast that is what I think it is. I noticed the other day when the muffler man was was fixing my exhaust that there was a hose that looks like it connects to the rear axel and I asked if it was a bad ting for it to not be connected and he said it was fine. That just sounds weird to me, what should I do?

 

No because it is the vent. When the axle heats up, it has to breath or it could easily pop a seal from the pressure. That is also why that if you ever go through water high enough that the end of the tube is submerged, you better change your diff fluid.