Many Fords come equipped with 100K mile platinum plugs. Changing them is seldom a problem…Today, most spark-plugs use a tapered seat which forms a perfect seal. No amount of PB Blaster can penetrate a perfect seal. That’s a waste of time. The penetrating oil will never get to the threads. After you break them loose, THEN a little Blaster can do it’s job and make removal a little easier and reduce the chances of thread damage. Instead of using 3/8 inch drive tools, try using 1/2 inch drive sockets which provides the leverage needed to break stubborn plugs loose. An often overlooked technique is to TIGHTEN the plugs a tiny bit first THEN back them out a quarter turn THEN spray some Blaster on them…
Consumers are fed up with high-maintenance automobiles. In the near future, cars will gravitate towards the goal of ZERO maintenance (like your dishwasher and washing machine) in order to sell their product in a VERY competitive market…