front and smells like brake? i have a 2003 ford f250 6.0 l diesel. when i activate my 4x4 and drive the front where the shaft is grinds, the part that goes into the transfer case. When it grinds it makes popping noises and smells kinda like brakes. I dont know what this is and i really dont want to take it into ford so they can charge me a arm and a leg to tell me what is wrong with it. Can someone please help!!!