Did you have the clutch replaced when you did the trans? Alot of times if the clutch is not releasing completey (do to various reasons such as warped disk, mis-adjusted clutch, bad slave, dirty input shaft where the disk cannot slide freely ect. is the prominent reason that the syncros wear. If your not releasing it your making the gears/syncros/hubs work twice as hard to speed up the next gear change. Can also be due to poor driving habits as in not fully pushing the clutch all the way in when changing gears. Should it have worn out again that quicky? probably not but something is making it wear premature. Do you have a list of parts that were replaced?
