Spark Plug Recommendation

[Johnny O]

I wouldn't run them to 100k simply because that's when they get stuck and break off. Put anti-seize on the threads too. I have NGK Iridiums in my V6 simply because that's all NAPA had that day to fit my truck, been in for two years and have no issues.

 

[Robert Caffyn]

OK, lets settle this! In mid year production 2008, Ford changed the plugs to a one piece design. So therefore, any vehicle made after January 2008 has the new plugs. This is all Ford is selling for the 4.6L right now. Still would change them @30-40K miles though. Bob :argue:

 

[Supercharged SVT]

Thank You Bob!

 

[Vic Sorlie]

RockAuto search shows two choices of Motorcraft plugs: SP509 and SP514. Both are listed for 08 4.6L V8. Differentiation seems to be on color of coil boot, brown for 509, black for 514. I'm guessing I should pull one of mine to see what color they are. Can anyone enlighten me as to the difference?

 

[scott degroot]

???