What was found
THE NR 2 ENGINE TRANSMISSION TEMPERATURE EXCEEDED UPPER TEMPERATURE LIMIT IN FLIGHT RESULTING IN PILOTS INITIATING ENGINE XMSN HOT EMERGENCY PROCEDURES AND RETURNING TO BASE FOR AN UNSCHEDULED LANDING. REMOVED THE NR 2 ENGINE TRANSMISSION ASSEMBLY AS UNSERVICEABLE IAW NEVER EXCEED TEMP LIMITS OF 234-2 MM AND REPLACED WITH A SERVICEABLE ASSEMBLY. DEFINITIVE CAUSE UNKNOWN AT THIS TIME PENDING COMPONENT DISASSEMBLY AND INSPECTION. AIRCRAFT WAS RETURNED TO SERVICE.