I see & hear a lot of stories about guys who have had to deal with the horror of pulling cylinder heads & so forth after the famous spark plug exodus.

My theory is, what is the best way to be proactive about keeping these things in where they should be.

My "L" is a 2001, so I feel it is a good time to have the old ones pulled out & put in some iridiums now.

So, do I simply put the new plugs in with some thread sealant? I'm not crazy about that theory. Or can I put in an insert before installing the new plugs.

I love my baby & want to keep it forever...as god intended.

What is the best advice?

 

you don't NEED to do an insert. If you check them often, make sure they're not just hand tight, then you should be fine. If you really want to fix the problem you could do a timesert setup or switch to 03-04 heads (8 threads instead of 3ish? if my memory is correct).

 

Just make sure they are installed right, and you won't have a problem.

 

While on the subject:

friend of mine has a 2001 as well. It's got almost 140,000 miles on it..and has never had a plug change, fuel filter, etc...and he just keeps beating on it. He wants me to change the plugs, clean the IC, and basically service it for him. There's good money involved so I will most likely not pass up the opportunity. Any of you guys have any suggestions I should look out for? Like stuck plugs, etc? 140,000 and not a single problem up until now...I think one plug is burned or just plain worn out. Should I go back with Motorcraft plugs or go with the NGK's? I put NGK's in my 2003....they seem to idle better but who knows how long they'll last.

 

There is an awfull lot of mis information on this subject. I for one appreciate a guy asking how to prevent this!

Yes it's true that the PI heads don't have that many threads. But there are some thing you can do that should result in a mild motor never having a problem.

1) Never ever over torque the plugs. (14ft lbs max) Just once is all it takes to yield the heads material.
2) Torque the plugs with the motor cold
3) Check them for torque retention from time to time.
4) If you still have the factory installed plugs.. check them for proper torque NOW.

Rich

 

So do the 2003 and 2004 lightnings not have this problem since they have more threads?

 

I have a 2003 and I threw a plug after a 300 mile trip heading back up to school. After high boost and heavy loads in Northern WV I hit a toll road in Pennsylvania and stopped to pay... I heard a pop then the truck starting limping. The threads in the head were fine, just had to get a new coil pack, plug threading back in with no problem and torqued fine. Now I keep my torque wrench with me and the tools to take care of a tick if I hear it.