Somebody correct me if I have it wrong but if you raise the front of the tractor and the fluid line finally appears in the sightglass, the fluid level is low, not high. If this happened after adding a gallon, the it was really low to begin with and still needs more. Unless the sightglass on the L2501 is ahead of the rear axle, not behind it like my L4610 had.At this point, I drove the front axel up onto ramps--effectively lifting the front end by about eight inches--and lo, and behold, a fluid line level was visible in the sight glass (maybe 1/4 way down from the top).
Okay. Now I realize I've got more than enough fluid.