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colliehauler's avatar
colliehauler
Explorer III
Jan 22, 2017

Ford V-10 sparkplugs (SP 479 or AP 103)

I bought a old X with the 6.8 and wondered what's the best sparkplug to run. I seen Motorcraft SP 479 and Autolite AP 103. Any suggestions?

I won't change them, I'll let the mechanic I use change the plugs and coils.
  • Before you do it, you'd better do some research on line about the blown out plug issue on the 2002 and earlier versions. There is a ton of info out there and it's not just a case of changing the plugs, there's a lot more to it. For sure Motorcraft but you might strip the threads taking them out plus there are special specs for installing the new ones.
  • I just did my plugs on 08 6.8. I was scared to death that they were 2 piece plugs but the weren't. I watched videos on youtube and just took time.. I used motorcraft plugs.
  • I used motorcraft on mine. I changed mine, its an 02, no big deal, use a torque wrench.
  • I think when I changed the plugs on our 2004 X the ford dealer told me to use SP479, it was 2 or 3 years ago. I changed them at about 120,000 miles and they all still looked OK.
  • Stick with the Motorcraft plugs and coils.
    I've seen issues with other brands