Joe, If the slack adjusters and the rod going to the S cam have been lubed that is likely rotating freely and probably doesn't have much wear.
But the rollers on the end of the shoes riding on the S cam are dry as is the S cam. If they aren't rolling freely, either in the end of the shoes or on the cam that is the area most likely to be the culprit. At least that's the way I read Hector's post.