So I recently sheared my rear output shaft on the NP231 in my 2002 TJ. I did an SYE swap and put it all back together. While testing out the 4WD I drove about 500 feet in 4L and it popped out gear and there was a slight clicking like it's just outta gear. The shifter is fully engaged. The shift fork spring has tension. Selector plate shows no sign of wear. The only thing out of the ordinary I was was the beveled ring that rides on the upper shift for shows signs of wear from what looks like the chain coming in contact with it.