What was found
AFTER REACHING CRUISE ALTITUDE OF FL330 ENROUTE, CAPTAIN OBSERVED RT ENGINE OIL PRESSURE FLUCTUATING FROM 42 TO 27 PSI. FLT CREW PERFORMED QRH & REDUCED THRUST ON RT ENGINE. JUST AS THE THRUST REDUCED, RT ENG LOW OIL PRESSURE MESSAGE ILLUMINATED FOR ABOUT 20 SECONDS & EXTINGUISHED. FLT CREW NOTIFIED CENTER & REQUESTED A LOWER ALTITUDE. FOLLOWING A DESCENT TO FL210, RT ENG OIL PRESSURE STILL FLUCTUATING. FLT CREW ELECTED TO DIVERT. A NORMAL APPROACH AND LANDING MADE. DETAILED TROUBLESHOOTING WAS PERFORMED ON ENGINE. BASED ON THE ENGINE'S HISTORY AS AN OIL CONSUMER & FAILURE OF NORMAL TROUBLESHOOTING PROCEDURES TO DETERMINE CAUSE OF PRESSURE FLUCTUATION, IT WAS DETERMINED TO REMOVE ENGINE.