What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: LOW PRESSURE LIGHTS ILLUMINATED ON BOTH THE SYSTEM A ENGINE DRIVEN PUMP AND ELECTRIC PUMP DURING GEAR RETRACTION ON TAKEOFF. HYDRAULIC INDICATION SHOWED AS LOW AS 1400 PSI BEFORE RECOVERING, LOW PRESSURE LIGHTS WERE ILLUMINATED. AIRCRAFT AIR INTERRUPTED BACK TO AND LANDED SAFELY AT DFW. REMOVED AND REPLACED LEFT HAND ENGINE (EDP)-ENGINE DRIVEN PUMP (AALA202604011429), PER AMM 29-11-11. ALSO, REMOVED AND REPLACED THE STANDBY EMDP LOW PRESSURE SWITCH (AALA202604146955), PER AMM 29-34-31. ALL OPS AND LEAK CHECKS GOOD.