Metal particles are the crud I was referring to, I'm hoping the bottom level fluid is as clear as the upper. I also plan on straining the gear oil through cheese cloth, just to see what is in there. Can't be too careful on a nearly 30 year old differential (or whole car for that matter).
I do remember on a Ford P/U I had, the syncros went south, and when I popped the top cover on that New Process 435, the gear oil looked like liquid gold from the brass/bronze syncro material emulsified in the gear oil, but that is another story.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.