Narrative:

While in cruise at FL320; eastbound in oceanic airspace; the left engine oil quantity began dropping. We monitored the loss and contacted dispatch and maintenance control (mc). We continued a dialog with mc as quantity continued to decrease. Oil pressure and temperature remained normal. Eventually oil quantity decreased to zero but pressure remained stable for about an hour. Dispatch and mc were kept in the loop. Oil pressure began to decrease but remained just above redline. Oil pressure yellow caution light began flickering. As long as the engine was still able to operate per QRH guidelines; we considered continuing to [destination]. But weather at destination was at CAT III minimums and forecasted to be that way at our arrival. [An enroute airport] was considered but due to weather and wet and shorter runway and a possible night single engine landing; we decided that our safest course of action was to proceed to ZZZ; which had good weather and long runway. We [advised ATC of emergency] and were cleared direct ZZZ. Engine remained operating and we made a normal landing. Upon investigation; ZZZ maintenance found no oil in the reservoir and oil dripping from the engine and cowling. We secured the aircraft and went to the hotel.

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Original NASA ASRS Text

Title: B767 flight crew reported loss of oil quantity from the left engine that resulted in a diversion.

Narrative: While in cruise at FL320; eastbound in oceanic airspace; the left engine oil quantity began dropping. We monitored the loss and contacted Dispatch and Maintenance Control (MC). We continued a dialog with MC as quantity continued to decrease. Oil pressure and temperature remained normal. Eventually oil quantity decreased to zero but pressure remained stable for about an hour. Dispatch and MC were kept in the loop. Oil pressure began to decrease but remained just above redline. Oil pressure yellow caution light began flickering. As long as the engine was still able to operate per QRH guidelines; we considered continuing to [destination]. But Weather at destination was at CAT III minimums and forecasted to be that way at our arrival. [An enroute airport] was considered but due to Weather and wet and shorter runway and a possible night single engine landing; we decided that our safest course of action was to proceed to ZZZ; which had good weather and long runway. We [advised ATC of emergency] and were cleared direct ZZZ. Engine remained operating and we made a normal landing. Upon investigation; ZZZ Maintenance found no oil in the reservoir and oil dripping from the engine and cowling. We secured the aircraft and went to the hotel.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.