Hi Ian,
After taking it apart, it appears the rubber diaphragm had a "flat spot" in the mold or the shock was assembled incorrectly from the factory. In effect...the diaphragm did not have a perfectly round lip,therefore fluid was seeping past it. You would think the metal cap would keep fluid in also but I never could get it to stop. Tried tightening it and also tried using thread lock. It slowed a bit but kept leaking. Is the NF unit any better in your opinion and does it mount the same way?? Thanks