[dkozloski]

Fifty or more years ago automotive shaft seals were made from leather. In fact, the largest producer was Chicago Rawhide. Leather seals were very reliable but would weep a very small amount of fluid. The answer was to change the sealing material to synthetic rubber or plastic. These seals can be made totally leak free but are not anywhere near as rugged as leather and are subject to catastrophic failures. Sometimes the best progress is a step backwards in time.