What I don't know about transmissions would fill the cloud, but I have experienced this code twice on the Winney. Once at about 215K, once at about 480K. In both instances the clutch friction packs were "replaced". The first incidence by replacing whole tranny, the second by doing a rebuild in local shop.
As I understand: The torque converter is filled with fluid from the internal pump, and the pump is driven through the various clutch packs from the converter,... as the packs wear (and lose thickness), there is less pumping pressure to fill the torque converter.
Things go down hill quickly from there ....
Even with clean Mobil 1 fluid, I don't expect much over 200K miles before another rebuild and friction pack replacement.