I'm currently at 148,000 + miles on my 2004 F150 and I figured it's time that I should change my spark plugs.

What is the gap for the plugs on the 2004 4.6? Do they list the gap spec. in my owners manual?

I already have the new plugs and the dielectric grease for the COP boots, so I should be ready to go out into the garage and change them tomorrow morning. Anything special I may not be thinking of?

 

After doing a little research it appears that my Motorcraft AGSF 32PM spark plug gap is to be .052 to .056.

 

The gap size specifications are under your hood, open it & look up, read the sticker.

 

After reading a different thread from a few days back, I'm curious to find out what the gap is on the plugs you pull out.

 

i changed mine out at 100,000 miles and the gap was huge but i cant remember exactly what it was. .052-.056 is the correct gap for a 4.6. the only advice i have is be careful when your screwing the coil back on. i was doing one of the hard to reach ones in the back on the passenger side and i guess the screw was cross threaded and it broke off. now i have a piece of wood wedged in between the coil and the fuel rail to hold it in place haha. theres just not any room to get any tools in there to remove the broken screw.

 

I changed the plugs yesterday and everything went fine.

The gaps were all different, which can be expected with 148,000 miles. On the old plugs, the smallest gap I measured was .060 and the largest gap was .082