Oil looked a little metallic, but nothing chunky.

Assuming a test drive reveals no other issues upstream, I'll probably dis-assemble both the 3.55s and my 2.76s for inspection and to swap sure grips (the 2.76s have a clutch). I won't mess with it until later this summer though. Have to get the Power Tour done first.

Probably be tomorrow or Saturday before I test drive it.

After letting the oil settle a bit, I poured it out. Found some metal chips in the bottom of the pan.

Closer examination of the ring and pinion did not reveal any damage. Maybe a bearing spalling up.

The test drive with the 2.76 member demonstrated none of the previous symptoms, so the issue does seem to be confined to the 3.55 member.

Next step will be dis-assembly, but probably not anytime soon.