Mostly successful 5.4L 3V spark plug change

[fizassist]

Well, that took a while. 86000 miles. 7 came out fine, one with a "stage 1" failure (porcelain intact). My procedure (basically the TSB): Run a can of Seafoam through the gas tank the prior week. Yes, it's probably just snake oil, but... Warm up engine a little (coolant temp to 100F) because it was pretty cool here this morning. This probably did nothing as the head was still cold afterwards. Unmount computer and bracket (leaving cables plugged in), remove a few vacuum lines and a grounding strap that were in the way. Remove COPs. Loosen the plugs 1/4 turn. 5 squeaked, 3 didn't. I assumed 3 were broken. The OTC6900 tool wasn't horribly useful here because I always needed some extensions. Poured 1 teaspoon of B12 Chemtool down each hole. I picked this because it had the most carcinogens, er, solvents of any product at Autozone in a non-aerosol can. Waited an hour and a half. Tightened and then loosened plugs until they started moving easier. One failure. There was no real correlation between how much the plug squeaked and whether it broke, in my experience. I had two that didn't squeak at all but came out fine. The one that broke sounded just like two others that didn't (no squeaking on the first 1/4 turn, but then started after the solvent soak). Curse profusely. After trial and error on the size, tapped the shield with a 3/8" NC tap (see bottom "tool"). Used combination of 1/2" square tube, a 19mm deep socket, and some 3/8" all-thread to extract the shield from the hole (see top "tool"). Put in new sp-507 plugs (with anti-seize on the shield). The OTC6900 tool was very useful here for retaining the plugs as I inserted them into the holes and threading them by hand. Even without the failure, this would have been a long job. (I'm used to I4 engines, what can I say?) Anyway, I started about 9 and got done by 5, and I'm still richer than if I'd taken it to a dealer.

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[Bluejay]

Good job! Glad you got them out successfully. Also, nice write-up.