I'm a bit floored right now. I got the skid plate off and found a bolt for the tranny mount and half of Eastern Washington. Cleaning as I went seemed like the right way to approach this and, considering what I found inside the TC, I think it was the best way also.
After I got the forest floor out of the skid plate I attacked the outside of the TC oil pan with a large wire brush to knock off the worst of the grit and grime around the bolts and the edge of the pan. Another good move as it turns out. Once the outside around the pan was clean, I pulled the drain plug again and let the residual oil drain while I losened the bolts. With a little coaxing the pan came right off and inside the bottom of the pan I found...nothing but oil, and maybe some tiny flakes of metal.
As a point of reference for the inspection I based everything off of what I believe to be oil holes in the intermediate gear. There are two and conveniently they are 180 degrees apart. I shifted the TC into 4lo to ensure that all gears would turn at once. Then while turning the front driveshaft by hand I started inspecting the teeth of each gear, ensuring that the intermediate gear got four full revolutions. I did this by counting each time I saw an oil hole come around. (Eight times = 4 full revolutions.) I checked the mesh of each gear this way. I found no gears with broken teeth. I felt in up underneath the gears for the rear driveshaft and also found nothing. I found no evidence of serious damage on any of the gears. These pics show the only 'abnormal' tooth wear that I found.
This bottome one gives a close-up of the holes I am talking about. You can also see that the oil looked fine for the most part.
You can see where the corners of all three gears for 4lo have all been ground down some. I believe that this is where the metal I found originated. I thought that maybe I was missing something. So I checked each gear twice. Then I went and started tracing wires to find a good place to start fixing bad places in some of the lighting wiring. After about an hour or so, I got back under the cj and checked each of the gears again. I made sure the front hubs were unlocked and checked the feel of the tc in each of the gears: 4hi, 2hi, n, and 4lo. Everything felt nice and smooth. I checked for excessive play the in bearing mesh, I did nothing scientific here, just a visual inspection while physically rocking a gear back and forth while holding the other. All of them had some but a not much.
I have a theory as to what the PO saw/experienced to make him think that there was an issue with the TC:
The tc shifts into all gears, but 4hi and 4lo are at the extreme e4nds of the range of motion for the shifter. The tc shifter linkage under the cj has a large amount of gunk caked on. The
Transmission mount had
no bolts mounting it to the
Transmission , leaving it free to flop around as directed by the motor and driver. I think that these things combined to make the tc difficult if not impossible to shift fully into 4lo or 4hi, or could have even caused it to occasionally jump out of gear. Judging by the gears, I am thinking that 4lo was where he had the most dificulty.
At this point, I think I might be ready to cut a gasket for the TC oil pan, clean any debris I might have left off the gears, reinstall the pan and fill it full of oil.