the chevrolet gearbox th 400 is equipped with an o-ring on the gearbox output shaft in front of the gearing. for what is the intended ? in the mounted gearbox output cover the bronze socket is pressed with the lubricating groove, which has a larger diameter than the outer diameter of the o-ring. why is this o-ring on the shaft ?https://img.motor-talk.de/JxhW6E6bUHEE9eFS.10.jpghttps://img.motor-talk.de/JxhW6BGk4o5ghlSa.10.jpg