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Ok So i have a 2007 3v F-150. 116k miles. Its my baby..... wife bought it for me brand new after one of my deployments to Iraq. The truck is bone stock and has been absolutely flawless other than one minor electrical issue i fixed myself(broken wire in door jamb harness). It only been back to the dealer once at 68K miles to have the plugs changed. At that point it still had the factory plugs in it and they broke 3 trying to get them out. Supposedly they installed an updated plug set. Well I want to change them again.... what are the odds they will break this time? I would prefer to change them myself this time. What are opinions as i have heard both good and bad about the updated Motorcraft plugs and well as good and bads about the champion plugs....
So.... who's running what and how much luck have you had with updated plugs?
First update with Motorcraft plus was from OEM SP-507 to SP-515. In last couple years, they came out with a newer design, some say it's one piece SP-546. I just did my '07 in July at 67,555 miles, removing SP-507s and putting in SP-546s. I had a Lisle 65600 tool set and because #8 broke leaving the porcelain and conductor in the head, I ordered Lisle 65710 porcelain puller to go with my set, which is what (#s 65600 + 65710) it takes to make the Lisle 65700 kit … which, if I was buying now is how I would do it. We also have a Mustang GT with the same type of plugs (it's a 4.6 3V) so I'll feel more better changing it's plugs, as if any break, this kit will handle it with ease. Once you use the kit, if you use the kit, you'll see it's not near as bad as we all dreaded.
That #8 … the porcelain puller clips on top of the electrode and you use the puller tube and nut (and after putting the tube on, it can't let go) … then pulls the porcelain and electrode out from places you can't see, then you can use the pusher on what is left, and extractor to pull barrel out. Ford book said use pliars, but #8 is way back under the firewall, and way down a hole.
My #2 also broke, but it broke the whole top off the normal way.
Wish I knew what to tell you … … some say the SP-515s break sometimes too. (I guess it depends on if they used the nickle anti seize on the barrel below threads) … … but then others say it only happens with the original plugs?
Notice that the way they are made, the newest SP-546s will compress the coil spring above it a little more for better contact I guess.
I had bought the SP-515s when they were the latest upgrade in 2016 or 2017 planning a change, but then saw someplace mention of newer SP-546, so I researched and … obtained a set of them. I guess I'll just maybe sell the SP-515s on CL?
