So this past weekend I was travelling down a hill in first gear in low range. The hill was steep and the surface was loose. When the Jeep started to slide partway down the hill I disengaged the clutch and hung on for the rollercoaster ride. Just before I reached the bottom there was a bang. When I got stopped the clutch pedal wouldn't depress to disengage the clutch. My first thought was the throwout bearing had gone astray.
These pictures are what I found this evening when I pulled the tranny. Notice the dust and gouges in the pressure plate housing
This is the way the pressure plate came off - actually had to pry pieces of the clutch off with a screwdriver.
Couldn't disengage the clutch but we managed to wheel for another few hours after this happened by starting up in gear. A real good reason to disconnect the neutral safety switch.
Based on my gearing and a potential speed of 50 km/hr at the bottom of the hill the clutch would have been spinning at over 15,000 rpm when it decided enough was enough.
Lesson - if when travelling down hill there is a need to free wheel remember to knock the transmission out of gear.