Why would oil turn dirty brown? I know its probably just dirty but this is a colour I haven't seen before...like muddy rain puddle colour.
Condensation sounds spot on....it's been raining for 2weeks here...the bus is in a garage but has probobly got damp....we are up on a mountain.
...unless you've got a Subaru conversion. After a while they commit seppuku, in a ceremony called "心を裂く" - ripping the heart out. The dishonour of being stuffed into an old van is simply too great for them.
You have. the oil is supposed to be on the inside short distances or no stat fitted dont help the milky oil especially in colder climates.