Quick question. Getting ready to order plugs from either 1stfordparts.com or fordparts.com

I have a 2004 Supercrew, 4x4, 5.4ltr. A prior poster listed the Motorcraft replacement plug part no. as SP-462. I contacted 1stfordparts by email, they responded by telling me the correct part no. is SP-421. I did provide them with my year no., VIN, etc.

Which is correct? What are the differences in these plugs? With the time and effort I'm putting into making sure I don't screw this project up, I want to make sure I have the right plug.

Thanks!

 

sp-421 is the correct # bud.

 

The previous plug was +1 step heat range hotter.

 

Thanks for the responses guys.

Enormous, the system won't let me send a PM since I've got less than 100 posts. PM me if you can.

Thanks.

 

you can also get them at Oreilly's the # is PZT2F in motorcraft