Spark Plug Troubles
I've owned my '06 E350 5.4L gasser for about two years. Ashamedly, I'm just getting around to a tune up. This past weekend I changed the plugs, fuel filter and air filter. I got to the last plug, number 3 (third one back on the passenger side) and it wasn't very tight. I kept turning the ratchet and it wouldn't come out. I kept turning and turning and nothing, the plug is stripped and won't tighten or loosen.
I'm guessing the threads are stripped in the head or possibly it's been repaired in the past with the rethread insert. I put it all back together and it runs ok, no noticeable difference in performance.
Has anyone gone through this before?