Spark Plug part numbers?

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Pinned

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Wanting to change my spark plugs soon on my 2018, just want to go with stock plugs as they've been totally fine the last 70k miles. I see both SP-550-X and SP-594 listed as stock part numbers. Which one is correct?

Also, do either of these come pre-gapped correctly? If not, does anyone have a factory service manual page showing the gap, torque spec, etc?

Thanks all!
 

nikhsub1

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FiveOsvt

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I have the SP-550…Anyone know what the difference is in part numbers, hotter, colder?
 

Hal993

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I'm living in the rabbit hole this first week.

Ford now lists SP-594 as the "service part". Factory installed for my 2020 was SP-578. Again, Ford currently lists the SP-594 as the Gen2/2020 spark plug for our trucks.

Go here and click on the red text and enter your VIN.
 
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