Earlier this year I was having problems with my t-case, I would put it in 4x4 and as soon as I put torque on it you would hear something grinding / skipping, so I dropped my t-case and took it apart. The chain was fine, no sign of it skipping, I did find that one of my syncro snap rings was sitting in the bottom of the case as well as 2 of the three clip that are held in by the snap ring. So I bought 2 new snap rings and 3 of the clips, put everything back together thinking that the grinding was the syncro not staying engaged due to the missing snap ring and clips and guess what, same thing. As soon as there is any torque put on the t-case in 4x4 you hear the grinding and have now power delivered to the front wheels. Any thoughts, my t-case is a np231 with vacuum shift. I'm asking because I am in the middle of doing some front end work and if there is a possibility that the problem could be there I might as well tackle it while in the area. Thanks, Steve