I recently upgraded my 425oz NEMA23 steppers to 620oz NEMA23 ClearPath servos, during the shake down phase, the Y axis consisting of leadscrews and two motors YL and YR will not remain parallel while either just moving the Y axis or during test cuts. In Mach3 the Y and A axis are slaved. I auto tuned the X axis, transferred the motor configuration to both Y motors, fined tuned the Y motors due to some humming. Machine is square and YL and YR are mechanically identical, motors are directly coupled to leadscrews. Executing a G0Y42 and G0Y0 command sequence ten times with spindle in middle of x axis; the result was a 5 to 8.5 mm un-parallel Y axis. Any suggestions or troubleshooting procedures would be greatly appreciated, as I'm moving from just Operator to Operator/Technician of the machine.