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 t...
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From Wikipedia
I'm not sure it is "official" from Ford, but most mechanics just use a 3/8" impact on the plugs in a hot engine.
3-valve 5.4 L and 6.8 L engines built before 10/9/07 and 3-valve 4.6 Ls built before 11/30/07 found in many 2004–2008 Ford, Lincoln, and Mercury vehicles have an issue with difficult-to-remove spark plugs, which can cause part of the spark plug to become seized in the cylinder head. The source of the problem is a unique plug design that uses a 2-piece shell, which often separates, leaving the lower portion of the spark plug stuck deep in the engine's cylinder head. The 2-piece OE spark plug design is intrinsically flawed, thus making it susceptible to this problem. Ford acknowledges this issue in TSB 08-7-6 as well as earlier TSBs. Ford's TSB does not state that this issue is caused by owner neglect. The TSB provides a special procedure for spark plug removal on these engines.
I'm not sure it is "official" from Ford, but most mechanics just use a 3/8" impact on the plugs in a hot engine.
