Originally Posted by
79pmooney
The older Treks has shallower letters and didn't have the issue. ThHe deeply lettered caps that cracked were only used a few years after which Trek went to the lugged seatstay ends. I think the next year. (I suspect the cracking issue had a lot to do with Trek going into a whole new process for attaching seatstays. Yes, better for production etc, but often there's a driving force behind such moves.)
FWIW, the rear triangle assemblies for the 6nn series frames prior to the socketed seat lugs were brazed in Japan and used a different supplier for the seat stay caps than the Waterloo-brazed frames (7nn and 9nn series).