What was found
RIGHT FMC FAILED. RTFL. CYCLED C/B FOR RIGHT FMC, MESSAGE CLEARED AND OPS CHECKS GOOD. RT FMC NEEDS PRECAUTIONARY REPLACEMENT DUE TO FMC FAILURE IN FLIGHT. REPLACED RT FMC. CLOSED BOTH BREAKERS FMC WILL NOT SYNC GIVES MESSAGE RESYNC FAILED SINGLE FMC WITH RT FMC FAILED EICAS. WITH JUST RT BREAKER IN RT OPERATES WITH CORRECT OPS SOFTWARE PN DISPLAYED. NAV DATA DRAG FACTOR AND FF FACTOR INCORRECT. REPLACED FMC. CORRECT OP SOFTWARE INSTALLED PS4052970-959. FMC CHECKS OK, NO FAULT LIGHTS.