How steep is to steep? Oil leak

[Late31ugh?]

Hi I have read steep hills will cause an oil leak. How steep are we talking? I had a puzzling oil leak that left a trail of oil. We went up a hill several times in the neighborhood that has a good 30 - 35 degree incline. The engine was also getting hot so the oil was most likely starting to get thin. Will this steep of grade cause a leak out of the rear of the engine?

 

[nkaminar]

It might. The rear main bearing seal is a really simple device. It is a labyrinth design with a drain, not the lip seal used in modern cars. It works well when it works and there are no parts to wear out. It does not work when there is too much leakage out the rear main bearing or when the breather is clogged or there is too much oil in the engine or the little drain tube is clogged. The steep hills you describe may overwhelm the system and cause a leak out the rear.