I tried removing the bolts on my pro4x... I just wanted to remove the light cover/wind dam because I wanted to replace the stock pro4x lights. The first two bolts I tried free spun, I came on here and saw it was a common problem. Long story short... I took it to the Nissan dealership. I complained that the bolt had to be removable if you were to change burned out bulbs. I told them I tried two bolts and stopped. I let them try the remaining bolts and they too could not remove them. The dealership is now replacing the entire roof rack. They sent it to a body shop to remove the old one and to weld the nuts on the inside. Because they are welding they are repainting the roof too. The best news: it's all covered under the warranty!!! I've been without my truck now for 2 weeks while this repair is happening, but the dealership has put me in a brand new armada platinum edition (which is pretty sweet). So if you are still under warranty and you plan on changing racks in the future, you might want to go ahead and try a bolt now. If you try one and it doesn't come out, STOP. Take it to the dealership and let them try other bolts. If they see all the bolts are marked up from you trying to remove them they will blame it on you for cross threading or over tighting the bolts. They tried that with me at the beginning but there were no skuffs on any bolts except the two I tried, and I finally got them to accept that it was not my fault.