Correct me if wrong here but doesn't pressure testing only diagnose half of the possible problems? If it passes the pressure test,yeah...it will not leak oil. What about the other half which is water coming in? Seems to me that a vacuum check would also be in order. There are two seals on the shafts,one facing in which holds oil in,one facing out keeping water from entering case. Every LU I have checked that was full of water,there was no oil leakage whatsoever. So...pressure testing if the LU has water in the lube is basically meaningless if this testing is what I understand it to be.