As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RT HDY QTY DECREASED TO 0.13 QTY STABLE WITH ENGINE DRIVEN PUMP OFF. OCCURED AT FL310 AT FL 310 STABLIZED IN CRUISE 40 MIN INTO FLT. REPLACED RIGHT ENGINE DRIVEN PUMP, PRESSURE FILTER AND CASE DRAIN FILTER. SYSTEM SERVICED, OPS CHECK GOOD AFTER ENGINE RUN.