I had a bad passenger side cable and upon replacement, managed to break one of pivots ends on the same side. Last week I got the new pivot ends in and finished the job. While I had things apart, I greased the rails and the pivot ends with white lithium grease. I can't really say I noted any real improvement but at least I know its been tended to.
dghii
2000 Boxster S 6speed 112k miles