What was found
NLG COLLAPSED AFTER PUSH BACK. R & R OLEO STRUT, MAIN DRAG LEG AND LOCKING STRUT, 2NDARY DRAG LEG & LOCKING STRUT, DWN TENSION SPRINGS, DWN-UNLCK ACTUATOR, ACTUATING CYLINDER. R & R MLG CONTROL LEVER , LGEU, MLG SOLENOID VALVE & CHECK VALVE. DFDR & CMC DWNLOADED, REMOVED TOW BAR & INSPECTED, NLG BAY & OLD NLG ASSY INSPECTED. NO DEFECTS NOTED BEFORE REMOVAL. INSPECT NLG DOORS & ATTACH FITT, NO DEFECTS NOTED. DREW SAMPLES FROM NR 1 HYD SYS. MANUFACTURE REQUEST A SIM PUSHBACK & TAXI, OPS CHECKED OK, & MANUFACTURE REQUESTED CHECK OF WIRING OF MLG EXTEND/RETRACT SYS IAW WIRING MANUAL. A/C FERRIED TO IAH TO COMPLY WITH REQUEST. IAH MAINT REPORTED NO DEFECTS OR FAULTS. AIRCRAFT RETURNED TO SERVICE. SDR OPEN.