Crashbox with added value
 

So, here's the "upper" shift lever pin of my 4 speed spur gear box next to the one I found inside while draining the oil:
https://up.picr.de/34027392kd.jpg

It sat in the rear bottom corner at the drain plug. Was buried in sludge and I only found it when "examinating" that sludge with my finger....

With the inspection cover removed, luckily it seems not to have travelled much through the gears, as I found no obvious chipped teeth or coarse shavings in the oil - other than very fine flakes from former grindiing while shifting.

The lesson is, expect the unexpected in Trucks 70 years old, and take nothing for granted. And better take apart everything. I never would dare to drive the truck when this pin has just fallen into the gear box (which they very easily do!). Some previos owner or his garage mechanic thought different..... picked another one from the shelf .... and got away with it.






Although having plenty of them, I made a third one of a drill bit shaft without the wear marks.

You're very lucky! That could have done some real damage. I'd be concerned that a drill bit would be brittle, you can get the correct pin from Van Pelt's for $2. p/n B-7221

I imagine that the day the pin was dropped into the case, a flurry of period-correct obscenities followed it down to the bottom of the case.

LOL!! Or maybe the mechanic in period-correct coveralls looked over each shoulder for his foreman, grabbed another off the shelf real quick, and put it back together without telling anyone.

Definitely lucky it didn't get mashed up in the gears. Guess sludge can serve some use at times, kept this thing from flying around in the box.