I was wondering if someone out there had an understanding of how the 4wd system works in a 93 explorer 4x4 with auto hubs. I understand the push button on the dash, the computer in the back, and the 4x4 shift motor. How does it work beyond that? once the transfer case begins to turn what happens? How do the shafts that connect to the front tires work? Am I right that the shaft going to the passenger wheel is a 2 piece shaft? How does it engage the hub assmebly on the passenger side? When I engage 4wd the two piece shaft spins freely (not together as if they are connected, basically the t-case side shaft spins and the wheel side shaft does not). It looks as though the shaft coming from the hub side, slides into the shaft coming from the t-case side. Is this right? It's kind of hard to see due to the rubber boot covering the connection. Does anyone know how the system works when working properly. Oh you might of guessed, my 4wd does not work. But t-case does engage and turn! This may be helpful too, when engaging 4wd I can hear a slight click coming from the drivers side thus assuming that side is engaging but nothing from passenger side. I'm thinking the problem is with the 2 piece shaft that powers the front passenger side wheel. Any help is much appreciated!!