Any relationship between altitude/elevation and oil leaks?

[blue2000s]

Originally Posted by JTP

Unless you have air in your oil lines, the altitude would not affect oil pressure to any noticeable degree.
It is unlikely altitude has any bearing on the oil leak. The engine is not a completely closed system. When the engine shuts down, the internal crankcase pressure slowly equalizes with the surrounding atmospheric pressure. While at operating temperatures, the pressure differential between the environment and crankcase interior is about the same whether you are at sea level or in Colorado.

It is most likely just happenstance that both of your cars are doing this. It could be that the seals were 'just about' to go, and the 100 mile drive into the mountains along with the cold temperatures (a big maybe on the temps) forced the seals to finally give.

Also, did you change the oil once you got to Colorado? If so, did you change the type of oil?

+1, the pressure difference that the seals see is the same at any altitude.