As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK, LEFT HYDRAULIC QUANTITY LOSS. T/S & FOUND HYD LEAKING AT THE L/H ENG STRUT HYD. BAY. OPENED & IN- SPECTED, FOUND DIFF PRESS IND. ON PRESS & DRAIN CASE FILTER MODULE LEAKING. R/R D.P.I. AS PER AMM 29-11-17-4; LEAK CK'D SATIS.