Possible cause of failure:
#1 & #2 front bearings are worn and are severely fretted on the OD.
Rear balance ring is oversized and fretted.
Drawbar shaft is worn. Drawbar has low force
Taper has 10 microns run out. OD of shaft nose and ID of front cover have rubout.
Grippers and Belleville’s are worn. Actuator push ring assembly missingRecommended action:
Clean, inspect overall dimensions. Replace bearings.
Grind chrome plate and regrind rear balance ring. Grind chrome plate and regrind drawbar shaft.
Kiss grind shaft taper. Kiss grind rubout on shaft nose OD & front cover ID.
Adjust preload, balance, assemble and break in. Final quality control inspection.