What was found
ON LANDING, AROUND 80 KTS, LOST ALL NOSEWHEEL STEERING. ACFT PULLED RIGHT THEN TURNED LEFT HAD TO USE DIFFERENTIAL BRAKING TO KEEP ACFT ON RUNWAY. FOUND THE ROD END OF BALL SWIVEL HAD COME OFF. BALL SWIVEL ALSO ATTACHES TO CONTROL ASSY POWER STEERING DRIVE CABLE. REMOVED CABLE MOUNTING BRACKET, REMOVED CABLE SWIVEL AND SPRING. INSTALLED NEW SPRING AND INSTALLED CABLE ASSY.