If its not giving you any problems then just replace the seal. Even if its missing teeth or whatever and its not acting up just run it. Normally the original New Departure bearings are better than any bearing that come in a rebuild “kit”. I have done a few Saginaw's, Muncie's and my newer T56 and usually the old sloppy transmissions really don't care about much as long as the parts in it are spinning and exist. If its not popping out of high gear then its probably all good.
