What was found
PDIS 974 27-50 9266 12APR23 MEM FACT U ON APPROACH AT FLAP EXTENSION TO FLAPS 1, RECEIVED A TE FLAP DISAGREE. DISCONTINUED APPROACH. COMPLIED WITH THE QRH, DECLARED AN EMERGENCY CHOSE 36C INSTEAD OF 36L. THE ALTERNATE SLAT/FLAP SYSTEM WORKED WELL, AND WE LANDED UNEVENTFULLY INTO MEMPHIS. ***EMERGENCY DECLARED*** FACT 12APR23 21:58 MEM U AMM: 12-13-06-3 AMM: 12-21-09-3 PERFORMED TRAILING EDGE FLAP TRANSMISSION OIL REPLENISHING ON BOTH WINGS PER 757 AMM 12-13-06-3 AND TRAILING EDGE FLAP SYSTEM LUBRICATION ON BOTH WINGS PER 757 AMM 12-21-09-3. BITE CHECKED ALL 3 BOXES, 305 FOUND ON FSEU 1 ON PREVIOUS HISTORY, REFERENCED FIM 27-51-00 FIG. 105.