[SCCAGT]

There is a TSB about it. Check the stickies. As for the dealer doing anything with the plugs at 30k, you can count on that they did not. As far as regular maintenance goes, the spark plugs themselves last for 100k. But the lifetime of the sparkplugs is not where the problem lies. The design of the plug itself is the problem for removal. So, the sooner you can get them out, the better. If pulling and cleaning the plugs frequently is not something you want to contend with, I strongly recommend getting a 1-piece design from Champion or Brisk. They are not cheap, but the future headaches far outweigh the cost of those plugs.