have the o5 5.4 and its starting to mis fire about to hit 85k and bought it with 79k. it ran great at 1st but now starting to act up. I plan to change the plugs and read all the fun articles anout how much of a pain it is!!! anyways when i look up the Spark plug #'s i find 3 different OEM motocraft plugs??

View
Image
12405 (SP-507)


Spark Plug
5.4L 3V V8 ; With Black Coil Boots
$19.16 Select a dealer for prices & availability
* Add To Cart View
Image SP-507


Spark Plug
5.4L 3V V8 ; With Black Coil Boots
$20.08


ford has 2 plugs listed on ford

*12405 (sp-507) 19.16 each
*sp-507 20.08each
*advanced sells part #sp515 (says this is the plug for the truck)
*than another part number appears #PZT14F

which one is it? im confused on something that should be simple!
thanks

 

SP-515 is what you want.

 

^ X2