As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LOSS OF HYDRAULICS DURING CLIMB, HAPPENED ABOUT WHEN GEAR UPLATCH CHECK WAS ACCOMPLISHED. DURING HYDRAULIC PRESSURE CHECK (TERMINAL AREA) HYDRAULIC QUANTITY DECREASED. FOUND SLOT CONTROL VALVE SEALS LEAKING. REPACKED VALVE. SERVICED HYDRAULIC SYSTEM. SYSTEM CHECKED GOOD IAW DC-8 AMM 27-80-04-2.