Talked to ford dealership and some other auto places about spak plug removal on my 5.4. My '03 has close to 91,000 miles. They were telling me about threads being pulled out when removing spark plugs. They were telling me about dissimilar metals welding together. Have any of you that replaced your plugs experienced this? I got quotes $300 - $400 plus $98 per cylinder if rethreading is needed.

 

If the plugs are those damnable two-piece things used in several year models of the 5.4L, I'd suggest letting a pro do the work. If you try to change them out and one of them breaks, you will pay the freight to make the necessary repairs. If the pro/dealer breaks a plug, he makes good on the repair.

I wouldn't enter into a contract to have a pro/dealer do the work without some form of guarantee. He could break a plug, then hold you up for more money to pay for something he did.