I just bought a 08 Expedition with 20,000 miles on it. I know about the spark plug issue on these engines built before the new style plugs were introduced prior to October 09, 2007. Well I just found out my truck was built on October 02,2007, and the engine was built late September 2007, and thus would confirm I have the ones prone to be problematic.....great(sarcasm obviously). Would you guys recommend trying to remove them now and replacing them with the new style, or just run em till they need replacing and deal with it then??

 

I have an 08 Mustang that is effected by the Spark plug issue. I used the SB procedure to remove and anti sieze the sheath of the plug at 2000 miles and just reinstalled the same plugs, I could see carbon at 2000 miles.
I am under the impression that there is not a new plug, but rather a technique for removal (service bulletin), and a means for preventing the carbon build up in the future (nickel anti seize). The newer plugs I believe fit a newer style cam in the engine, therefore not letting you just replace the problematic plugs with a newer style. Please correct me if I'm wrong.