The first cylinder I tested, was the 130 psi and the gauge held it until I released it with the needle valve (tire valve) release. So I think you all may be right that I have a gauge issue.

Thanks for the clarification on the altitude too Tony. I was curious what that might be.

Is there a way to tell where the oil may be coming from (without pulling pieces)? I'm not opposed to pulling things, but if there's an easier check...
Thanks again!