I spotted some fresh transmission fluid around my pan gasket. Looking further, it looks like the vent holes at the bottom of the bellhousing are pretty wet and thick with dirt. I am assuming that I have a leaky seal around my torque converter and possibly front shaft seal. I will doublecheck the pan bolts, but I can't believe that the fluid is getting forward of the pan and onto the bellhousing.
1985 W126 380SE. BIG job (i.e. lots of cash involved)?
By the way, the transmission is behaving completely normally. I will keep it topped up until I get it serviced.