2008 F250 5.4
I changed all plugs to Champion 7989 1-piece a few years back at about 105,000 miles. A few months ago at about 135,000 miles one of the Champion plugs was causing misfire code and was cured with a new Champion plug. Now I'm thinking about replacing all plugs with Motorcraft. Or maybe just leave it be. There are not currently any codes on the Champion plugs but might Motorcraft work better. Hopefully Motorcraft is now a 1-piece plug too. Any feedback?

 

Motorcraft has had a 1 piece plug for the 3 valve motor for quite a while now modular motors are know to be picky about plugs the motorcrafts work and don't cost really anymore if any at all no reason not to use them.

 

Switch to Motorcraft.

 

I've only used Motorcraft in my Fords since the 60's .. Never an issue

 

I won't even put Champion plugs in my chain saw. Motorcraft or Denso is all I run as long as they make one for the application.

 

Motorcraft! Nothing else.