Finally got around to changing my plugs this weekend. Have 15,000 miles on car. All the plugs came out easily except for one. That one just had a little resistance on it, but nothing too bad. However, all the plugs did show noticeable carbon build up so I'm sure the problem would have gotten worse had a I continued to put it off.

Just wanted to pass the info on to anyone going back and forth with changing them. The sooner the better.

 

Yeah, I did mine at 7K miles with no problems. I plan to remove, inspect and reinstall my autolite HT0s every 7K miles and replace when necessary.

 

I've been dreading this myself. Coming up on 44K miles on the original plugs and I've noticed a small drop in mileage over the last couple of thousand miles... time for plugs... maybe I'll just let the stealership do it..

Congrats to the OP.. It's a hairy job.

 

Did mine at a little under 30k with no problems but I went into the matter knowing what too expect and just took my time and crossed my fingers...

 

I just traded in my 04 F150 with the 5.4 for my 10' GT and I changed the plugs in it right at 84K. I ended up breaking 4 plugs off. I followed the TSB word for word. I even had a fuel treatment done at ford. It didn't help any. I ended up getting all of them out no problem with the lisle tool. Still a pain.....

 

Dealerships are making people sign a waiver before they touch the plugs. Basically, "If we break it, it's your problem."

 

That just doesn't seem right! It's Ford's design and choice of plugs.

 

Its not right, I was quoted $90 per plug that broke off. I bought the removal tool for $75.
So if you add it all up for dealership costs: $225 for plug change, $110 fuel service treatment (recommended by ford), and $90 per plug that breaks. Best case scenario $335, worst case $1055..........thats what I was quoted for the F150 from the dealership.

 

If you follow the TSB on plug removal and take your time, most people get them out. The key is to let them soak a long time, I let mine sit for 2 hours after the initial break loose. Then turning them out a little, tighten slightly, a little at a time, if they get tough let them soak longer. Use a small torque wrench and do not exceed 25lbs on removal

 

I followed the TSB word for word and let them soak overnight, and used a torque wrench. Still broke 4. The most crucial part in the whole process is the first 1/4 turn that you make before you soak them.