If your story is that the leak is present when you go into driving mode and stops when you switch to leveling mode, and you are reasonably sure it is in the location of the rear spool valves, and it is not the blue 3/8 plastic line between the Norgren and the ride height valve, then the only other line energized in drive mode in that location would be the black 1/4 inch signal line going to that Norgren.