Looking for advice here. One of my Twin Disc MG502 gearboxes has about 1/16" of play at the driveshaft. In other words, if you apply axial force to the shaft, it moves in and out of the gearbox. The play is in the gearbox, not in a coupler, u-joint, etc. The other has no play at all. Here are my questions: How serious is this? Can I continue running without causing additional damage? What would have caused this, or is it within the tolerance specification and perfectly normal? Thanks in advance for the help.