No recent work done. Doesn't seem to be overfilled. Shifts great. Rubber oil sling gasket is still intact. Only seems to happen at elevation. I live at 4000ft and travel to about 7000ft for work. watch it pour out the shifter hole at approximately the same place on my route every morning. I installed a vent in the shift plate but didn't seem to make a difference.
Just looking for thoughts on possible causes.
Thanks