As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR RETURN TO OKC DUE TO GREEN HYD SYSTEM LOW ON FLUID. FERRIED TO MSP. FOUND STBY GEN SELECTOR VALVE LEAKING HYD FLUID. FROM LOG SHEET DISC 17: RESEALED RIGHT WING ROOT PER EOA57042 LEAK CHECK GOOD REMOVED AND REPLACED STBY GEN SELECTOR VALVE PN 71149-3 SN OFF F9818862 SN ON F971762. REMOVED AND REPLACED NR 3 ENG EDP PN 521449 SN OFF F9830152 SN ON F9829513 IAW 29-10-17 OPS AND LEAK CHECK GOOD.