What was found
FLT 231 FROM MIA TO PTY. AFTER TAKEOFF, NR 2 SLAT DID NOT RETRACT. CYCLED SYSTEM TWICE STILLS NO RETRACTION. FUEL WAS DUMPED AND THE AIRCRAFT RETURNED TO MIA WITHOUT INCIDENT. AIRCRAFT WAS INSPECTED AND THE NR 2 LEADING EDGE SLAT ACTUATOR WAS REPLACED. PERFORMED TEST FLIGHT AND WAS UNSUCCESSFUL. UPON FURTHER INSPECTION, FOUND THE FORWARD ROLLER TRACK BEARING SEIZED INBOARD AND OUTBOARD. REPLACED AND LUBED NR 2 SLAT BEARINGS AND NR 2 SLAT. ALL OPERATIONAL WORK CHECKS NORMAL IAW MM 27-81-11 AND 27-81-32. AIRCRAFT RETURNED TO SERVICE.