I changed the transaxle fluid in my mower this spring. Used castrol 5w50 synthetic. Everything went smoothly changing fluid and mower is running great, but there's a tiny little puddle of oil after every mowing. I have never measured how much (should have by now) is leaking, but it gets absorbed by the concrete floor. I can't tell where the origin of the leak is, but it drips off the bottom of the transaxle. There's a possibility I might have overfilled it, because I wasn't sure really where to measure the fluid when filling. Could it just be purging out excess fluid from the vent when warm? Seems like the oily spots are progressively smaller each time. It never leaked before. Anyone have any thoughts or similar experience?