i'm replacing my spark plugs soon and getting a parts list together. my buddy told me to get the f250 spark plugs to put in my 2004 f150 fx4. i was wondering if any of you all have any experience with this?

my trucks at 100,000 miles and i was also wondering what to do with the coils? is there a good way to test them to see which ones need replacing? or is there a general mileage to switch them out. i didn't see them in the manual for service.

thanks for the advice and help.

 

The engine determines the plug type, not the truck size.