After doing a search, I found plenty of people with similar but opposite problems, but only one person with this exact problem. Rather than bump an old thread where he wasn't the OP, I figured I'd start a new one. I bought my '14 SCrew with 54k miles on Sunday. This evening while coming up the driveway, I realized I hadn't tried 4 low yet. I put it in 4 high every day when I come home (gravel, half mile going up hill) and haven't had any issues. I got it in 4 high, drove a few feet and came to a rest, shifted to neutral, and put it in low side. Worked just find as I drove a hundred feet or so. Stopped, put the truck back in neutral, shifted to high side, and after being told the transfer case had shifted, I put it in drive. The speedometer indicated I was driving forward at 10 MPH, but the truck was actually in neutral and I was slowly rolling back. I shifted in and out of low and 4x4/4x2 a few times with no effect. Finally, I left it in 4 high and gunned the engine. At about 2000 RPM, it started grinding for a second or two and then jerked into gear. Once I got to my parking spot on top of the hill, I managed to get it to do the same thing on the second try. Again, I was sitting still, but it said I was driving at 10-15 MPH and the odometer even turned over a tenth of a mile. I managed to get it into 4 high by revving the engine again, and this time it engaged with less grinding, but grinding nonetheless. All that to ask, has anyone else had this exact issue? What ended up being the problem? I'm still covered by both Ford's powertrain and Carmax's warranties, so I'm not overly worried. It just really bugs me and I'd like to know a little bit more about the issue before I talk to a service writer.