Well, people are breaking them off with 30K, 60K and 90K miles on them so whats the difference. My point is simply, you don't have to replace if they are not broken.

 

All I can tell you is I have another engine. Enough said. Gotta love those spark plugs Ford, thank!

 

I worried for Years about getting these plugs changed. I had them done at 100k or so. Yea, some broke, but they have a way to get them out. It cost a couple hundred bucks... whatever. Definitely wasn't worth all the worrying.

There's no problem leaving them in passed 100k either. The plugs looked great when they came out (although in pcs). and I got no better mileage or engine performance after the change. I'll probably never change them again.

This is on 87 pump gas Every day of it's life.

 

My dealer wanted $399 for the plug change and then would have to discuss the cost associated with / if any broke. If I would have joined this site earlier, I would have known to get them out earlier. However, I was under the impression of 100K change, so there I was at 105K and the service manager at two dealerships said in their opinion, if the truck is running good, which it is, they suggested leaving well enough alone. My son couldnt get them out, I couldnt get them out and was afraid of breaking them, so now I am at 116K and all is well, for now! We shall see!

 

Ford should fix it for free. So much money we spend on out trucks and to have a bad head design is just wrong for them to charges us all that money because Ford ******* up! My truck has 58k and I'm starting to save up for the spark plug change also.