2002 Ford CVPI, 157K.
Out: Very black, thin compound of unknown grade, type and age. Evidence present of previous changes, thankfully.
In: Valvoline Synpower 75W90LS.
I actually hadnt intended to get gear oil, but I was perusing the selection at AZ and found the Synpower specified meeting SAE J2360. I was very surprised, so I decided on a whim to take some home and do a change. Glad I did after I saw what was in there.
The LSD seems content with the amount of FM present. No chattering or noise has been heard since. I have confirmed it still works too. Several times.