Just a thought with the reputation Ford has with breaking off spark plugs in the head when changing them, have any of you planned ahead and put a little never sieze on the threads and reinstalled? Seems to me this would be a good idea for reducing problems in the future.

 

that would only apply to 04-08 5.4L engines.

 

What makes the 5.4 prone to this and not the current engines?

 

And the 4.6 V8's and 6.8 V10 engines. The problem was a 2-piece shell spark plug, that was discontinued in new engines built in late 2007. We now have new engines and new spark plugs. Not all engines with these plugs had the problem...my early-year 2007 3-valve 4.6 V8 had the plugs changed at the recommended 100,000 miles without incident.

 

The design of the spark plug. The 5.4 plug has a longer throat past the threads with the electrode at the end. This throat is usually what would break in the head. this would corrode and bind to the block so when one went to remove depending on how long they've been in, it would break off. Where as the normal spark plug has the electrode right after the threads. Also the 5.4 plugs didn't use crush washers as normal plugs do, which helps keep the plugs tight but also AIDS in their removal.

 

The cyclone and coyote engines don't have this problem.

If it makes you feel better to never seize them, it won't hurt anything.

 

Good info. Thanks. I'm new to the Ford stuff. Drove GM for years with great success but couldn't resist this new design Ford. I love it.