Differential check. Seeing so much crud on the axle, I figured it was a good idea to check it. Good thing, it was about a pint low, with lots of metal specks in the black oil.
I brought the cover up to Pebble Beach concours standards, painted with black primer. LOL
I then removed about 5 pounds of crap off the axle, so it should handle much better. Don't think this had been worked on for decades.