During tapping cycle (with or without G84.2) our mill is screwing off

Error #11 motor over load comes up.. And/or C axis motor overload. The machine does mot have a C axis
The spindle seems to loose where it is pulsing forward and back (shaking motion) when tapping

Trying to job "Y" using the jog button ...... Once the button is released the table shakes back and forth very rapidly ( shaking motion ) after 10-15 seconds no alarms have come up E-stop gets hit to stop it

"X" axis sounds HORRID when jogged

Wondering where to start digging in ?

machine : VMC 15 Fadal mill been in use since 1999... Never abused ... Cuts brass / plastics 80% of the time

Thanks in advance all