What was found
FLIGHT 741 EN-ROUTE, ON TAKEOFF ACFT VIBRATED & OSCILLATED 3 - 4 DEG, PITCH UP & DOWN DURING GEAR RETRACTION. THE FLIGHT DECLARED AN EMER, RETURNED TO FIELD & LANDED WITHOUT FURTHER INCIDENT. DUE TO THE BRIEF & TRANSIENT NATURE OF THIS EVENT, TAKEOFF UNTIL WHEELS UP, IAW COMPANY REQUEST NOSE WHEELS REPLACED. SEE LOG PAGE 3123853 & 3123852 PILOT INDICATED NEGATIVE FLIGHT CONTROL OSCILLATION ON VIBRATION REPORTING FORM. NO REOCCURRENCE ON GEAR DOWN FOR LANDING & NO 30 DAY HISTORY.