Obsequious1

Thats when your number 3 or number 7 or any one for that matter, spark plug becomes loose, rattles from vibration, ruining your threads, then eventually blows out from combustion pressure.

Riggs

I know a lot of people who don't use anti seize but I would recommend it since my father had a truck that he couldn't get the spark plug out of the head. Took it to a shop and asked them to pull it out cause he was afraid of breaking the spark plug off in the head. Well it broke off at the shop. Thats the only reason I say to always use anti seize. To each their own though.

jtfrog

And just a touch of anti seize

Chris98Gt

I always just put a layer of anti-seize on mine and snug them down with a 3/8 drive rachet, never had any problems.

72MachOne99GT

*up to you*

I used it before and had the plug blow out of the head.

Last time after changing the head out of my car I just torqued them down to spec w/o anything on the threads.

X6StringerX

I decided that today was the day. I only ran into one minor hiccup. As I removed the #2 COP, the boot seperated from the coil and stayed attached to the plug. I wrapped some needle nosed pliers with a microfiber and gently pulled it out. I ended up tearing a small 1/2" chunk of the boot completely off. I thought all was lost, but I was able to reattach it with some Permatex. If it gives me any problems, I'll replace it, but as of now, it's functioning fine. It could just be a coincidence, but I thought it was odd that out of all of the COPs, this one was missing the Motorcraft sticker on top... maybe it was a generic replacement of inferior quality. Oh well.

BTW, the plugs were indeed the factory Motorcraft plugs. They had a purple dot on the top. 66k on them.

Veets44

I had one blow out last year right after I got it back on the road. It sucks, but my mechanic was able to re thread it, so it was a pretty cheap fix.

Good luck.

jivepepper

Mine blew out because of my car running lean.