[joeydurango]

Thanks, that's really helpful, especially the link to that old rebuild thread - I'd seen that years ago but had forgotten!

I've been running (fresh) 80-90 gear oil for a couple years now, nothing's different there. And the shifter works pretty smooth (for a 46-year-old truck, anyway)... I'll lube it for good measure.

Sure seemed like something changed abruptly, not a wear issue, but a breakage issue - and it happened immediately after a mild 4x4 session. The internals of the 205 seem pretty bomber, so I will check the shift pattern from below, and see if I can get to those detent balls without dropping the case.

Another train of thought - maybe the case has been intermittently spinning the front shaft all along and something else in the driveline has begun making noise, so only now I notice. As noted, though, everything else appears normal!

At least I've got a couple things to work with. Thank you again.