As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT DEPARTED RIL, FLIGHT NR 100, EN ROUTE TO DFW WHEN THE LEFT ENGINE OIL PRESSURE STARTED FLUCTUATING EXCESSIVELY. THE PILOT SHUTDOWN THE LEFT ENGINE AND RETURNED TO RIL WITHOUT FURTHER INCIDENT. UPON TROUBLESHOOTING, FOUND THE LEFT GEARBOX PRESSURE TRANSDUCER WAS BAD. REPLACED TRANSDUCER, GROUND RAN, ALL SYSTEMS CHECKED NORMAL. AIRCRAFT WAS RETURNED TO SERVICE. (M)