I found a fresh streak of grease splatting the underside, in-line with the "sliding sleeve lubrication fitting" i.e. zerk fitting just behind the flex coupling. There is a fair amount of it..maybe an ounce or so.

Any guidance on this?
EDIT - now that I'm looking at the photo again it looks lik the grease is coming from the seam immediately aft of the zerk fitting, no the fitting itself. Hmm. How worried should I be!?