91 ford f-150

there is a small hose that goes into the differential and clips to the frame but goes nowhere? It has a cap on the other end. I ask because mine was spliced and didn't know what it did or if I should be concerned. Thanks

 

sounds like a breather tube. it allows air to circulate. unless you do some offroading or its close to moving parts or exhaust, i wouldn't worry about it.

 

Worry about it. All you have to do is clip the end off clean, then put it back on the nipple on the axle tube. It's the vent hose. Note that the routing was revised in the 2nd diagram.

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