Mechanic told me that if my truck runs good then i should not worry about changing my plugs right now. but im right at 98K miles. my truck runs great, no problems what so ever. dealer quoted me at $300 for the plug change (parts & labor) and an additional $80 for every broken plug although this is a good price, money for me is getting tight while im in school so how long do yall think i can go on these plugs. im not looking to damage anything and ive heard these plugs break upon removal, so does this mean that i have a risk of them breaking while driving?? not sure if this helps but all the driving i do is highway. thanks guys

 

They will not break while driving. And, if you use gas with a good detergent and the tech knows what he is doing, should not break coming out. AS to how long, let the engine tell you. If it starts running worse and you start losing mpg, time to change. I know one member that went 133,000 and none broke coming out.

 

the longer you wait the more likely theyll get stuck comming out. Ford says they last 100k. Most of the dealers are pretty good at getting them out without breaking them and if they do break one they can get then out. I wouldnt wait to much longer.

 

I vote change them now. That guy with 130k+ got really lucky, but I'm happy for him. I plan on continuing to change mine on 50k intervals.

 

Changed mine at 135K. No problems. None broke. Did spray some penetrating lube then started the engine for about 5 min. Plugs looked good. Probably could have easily went to 150K. If it's running good don't mess with it.

 

Desert, you don't have the 3V engine if this is the truck in your profile. The 04+ 5.4's are 3v, and have a major breakage issue. Apples and oranges.

 

My 06 5.4 has been at the dealers for 2 days now to get the plugs changed. The service writer says they are having problems, first with getting the plugs out, now it has a skip.

Oh ya I have 13,650 miles on the truck, and I have had it 2 years.

100K plug interval my ****!

 

why would you get your plugs changed at 14k?

 

My first thought is that the tech does not know what he is doing. At my dealer, they have broken only 2 or 3 plugs and I know several have gone over 100,000. One I know had 133,000 on it. They changed the plugs in 2 hours, none breaking.

 

I think I smell a scam. Why would they sell you on a plug change that early then they have it for 2 days-make a big deal out of it. Crooked dealer I bet.