Anyone ever experience low oil pressure 10 hours after oil filter change? Gauges were checked with manual pressure gauge on each Engine three times and sending units were swapped and oil filters were changed. Local Volvo recommended using Volvo filters which I am doing today. His next suggestion was checking the four external relief valves. Hope he is right otherwise it’s the oil pump. Also was wondering about external engine oil filter, if it is cooking the oil, therefore rendering oil viscosity useless. My only problem with that is, why doesn’t Engine temperature gauge increase also, they stay constant at 180. But I did enjoy the 45 short trips and 100 NM in the last 2 1/2 months I have owned her.