What was found
FLIGHT 1793, CLT TO PHX, EICAS LT HYD QTY APPEARED, RAN QRM PROCEDURE. EICAS LT HYD ENG PUMP, RAN QRH PROCEDURE, LT HYD SYS PRESS RAN QRM PROCEDURE, PTU MAINTAINED NORMAL SYS PRESS UNTIL GEAR EXTENSION. EXTENDED GEAR & FLAPS VIA ALTERNATE PROCEDURES SUCCESSFULLY. R & R NR 1 ENG DRIVEN HYD PUMP. OPERATIONAL & LEAK CHECKED GOOD. FOUND DIFFERENTIAL INDICATOR AT NR 1 ENG HYD FILTER MODULE LEAKING. R & R O RING, LEAK CHECKED GOOD. R & R FILTERS AS PRECAUTION, NO CONTAMINATES FOUND. ACFT OK FOR SERVICE.