Thanks for a response, I don't know anything about these Oliver's. Where do they get their oil pressure from? I have noticed the oil pressure will drop before the rpm changes on a slite pull, and it feels like to me that I can feel a vibration at 1800 to 2000 rpm. I have used 20-40 and 20-50 oil and I have even put some STP oil treatment. The leak test, is that where you take and put transmission fluid under pressure? Where do you tap in the oil system? Thanks again. Ralph