Not running an alloy rad by any chance are you? That would explain the fans running on a standard rad switch as well. You might need a green switch if you are - from Stu.

How hot does she run and has the sender been changed of late? They can read lower when they age as a few folks on here have discovered - which can be misleading. Looks cooler than it is actually running.

If there is oil in the water the most likely trouble spot is the head gasket for sure - any water in the oil at all? The tests are for cylinder gasses so if there is a tiny oil leak it might not register as a problem... just yet at least.