A while back, I wrote an article about the importance of using dielectric grease when changing spark plug wires. What happened in the picture below is another reason to use dielectric grease. These spark plugs and wires were original in a 2008 Chevy Suburban 5.3 and were being replaced as normal periodic maintenance. Sometimes it’s tempting to just do the plugs and skip replacing the wires, but often the metal tip sticks to the spark plug so tightly that the end of the wire comes apart. If you want to try your luck with the spark plugs alone, check the price and availability on the wires just in case. There’s no coming back from this, so just be ready to pony up for a set of wires if you’re tackling your plugs this weekend.
Bonus tip: the white triangle on the tip of the spark plugs indicate they’re original. The AC Delco plugs you get from a parts store don’t have the triangle (at least I’ve never seen one).