Fellas/Ladies, not only am I new to the forum, but new to owning a four wheel drive full size ford. I have owned my 1989 Bronco XLT for about two weeks. I bought it with the knowledge that something was wrong with the transfer case, but for what I payed for it, I thought it would be worth it. I had my mechanic change valve cover gaskets and the steering column to solve an oil leak and get rid of the red neck vice grips on the starting rod on the top side of column. After that was fixed I decided to take the Bronco on a short trip to the gas station. 1/2 mile down the road in 2wheel drive I hear a loud pop under the floor board and the truck won't go, just engine revving. I pull into a drive way, move the shifter from drive to park and vehicle starts moving again. I drive back to my mechanics house. He begins checking the transfer case and tranny. The truck won't move now in 2wheel drive or 4wheel high but drives fine in 4wheel low. The tranny as far as I can tell is a C6 three speed auto and shifts out just fine. I'm open for any advice or suggestions. I also have a picture of the transfer case tag that I will post if I can figure out how to post it. Has anyone ran into this before?