What was found
CLT - FLT 1782 - CAPTAIN REPORTED THE NR 1 ENGINE EXPERIENCED COMPRESSOR STALLS AT FL 370, REPEATED AT FL 350, THEN A SUSTAINED SURGING AT FL 310. CREW ELECTED TO DIVERT TO CLT WHERE THE FLIGHT LANDED WITHOUT INCIDENT. NO EMERGENCY WAS DECLARED. DURING TAXI-IN, THE NR 1 ENGINE SUSTAINED A VIBRATION AND AN UNCONTROLLABLE EGT (733 AND CLIMBING). THE NR 1 ENGINE WAS SHUT DOWN AT THIS TIME. AIRCRAFT PROCEEDED TO TAXI TO THE GATE. MAINTENANCE REMOVED AND REPLACED THE NR 1 ENGINE ASSEMBLY PER JOB CARD. ENGINE RUN, OPERATIONAL CHECK AND LEAK CHECK GOOD. FOLLOW-UP REVEALED NR 4 BEARING FAILED PER OPERATOR P/P ENGINEER. (X)