What was found
(CAN) AFTER TAKEOFF, LANDING GEAR WOULD NOT RETRACT, RECYCLED DOWN, ON NEXT RETRACT NOSE GEAR UNSAFE LIGHT ON WITH OBVIOUS VIBRATION, QUICK REFERENCE HANDBOOK PROCEDURE CARRIED OUT, GEAR UNSAFE LIGHT WENT OUT. AIRCRAFT RETURNED TO BLOCKS. REPLACED BOTH NOSE WHEEL ASSEMBLIES, SERVICED NOSE OLEO, GEAR SWING CARRIED OUT, CHECKED SERVICEABLE.