As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LOST CENTER HYDRAULIC PRESSURE WHILE ENROUTE. FLIGHT CREW FOLLOWED AOM CHECKLIST AND CONTINUED TO OAK. DECLARED EMERGENCY. A/C TAXIED TO GATE UNDER OWN POWER. ACCOMPLISHED OPERATIONAL TEST OF CENTER HYDRAULIC SYSTEM PER B767 MM 29-11-00-5. NO FAULTS NOTED. CHANGED CENTER SYSTEM AND ADP PRESSURE SWITCHES PER B767 MM 29-31-01-4. EICAS MSG CLEARED.