Gulfstream V / G500 / G550
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 15; Flight Crew Total 7400; Flight Crew Type 100
Aircraft Equipment Problem Critical
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Overcame Equipment Problem; General Flight Cancelled / Delayed; General Maintenance Action
Aircraft
On an empty repositioning flight from ZZZ to ZZZ1 to then continuing on to ZZZZ. Preflight was normal; checking the site gauges on each engine indicated full oil quantities. After my walk around I briefed my First Officer that the preflight was normal and the oil quantities were full. Departure was uneventful and normal. I was flying the aircraft on autopilot navigating direct to ZZZ2 and we were in a normal cruise climb passing FL380 climbing to our assigned altitude of FL390 approximately 35 mins after departure from ZZZ when we noticed the oil pressure reducing rapidly to zero followed by the red CAS message 'right oil pressure low' The zeros turned to dashes and the CAS message and Master Warning extinguished. This happened a couple of times. Center cleared us to FL410 and we advised them that we would like to discontinue our climb and that we were working an issue. All engine parameters were normal except for the right engine oil pressure which was dashed and oil temp was slowly and steadily rising. I called for the oil pressure low checklist from the QRH. I continue to fly the aircraft on autopilot while my First Officer initiated the checklist in the QRH. We requested a diversion to ZZZ2 which was the closest suitable airport. We completed the Oil Pressure Low checklist verbatim and secured the right engine. Center gave us vectors for our descent for ZZZ2 due to being very close to the airport. We were cleared for the visual approach to Runway XXL backed up with the ILS an uneventful approach and landing was made without incident.
Captain reported a diversion and a precautionary landing after loss of engine oil quantity indication.