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Million dollar spark plug repair!

While having my 2007 Ford F-150 5.4L serviced at my Ford dealer, I asked this question. How much to change the spark plugs in this truck. The answer I got just about made me load my britches. The service manager told me it could cost up to $1000.00! This depending on how many spark plugs break during removal. Causing the cylinder to be cleaned out and possible re tapping. Is this true? I have no problem paying for the plugs and a reasonable amount of labor. If this is a true problem with these engines should the manufacturer help with these cost? I think so! Thanks for your time! mibloodhound

You know how everyone you ever met who has had a back injury has the story “The doctors said that I would never walk again, but here I am!” The doctors have to offer the worst-case scenario. It is bad for the patient because it crushes optimism, but they are far more worried about covering themselves against being blamed if things actually do turn out for the worst than they are about the patient’s attitude.

This is the same thing, except that the only thing that is hurt by this tactic is your trousers. If these are the original spark plugs in your truck, there is a reasonable chance that one or more of them will not come out. He does not want to be blamed if that happens.

I think you should take the truck to an independent mechanic and get a second opinion, in addition to another estimate.

Why would you go there for service if this is their pricing policy?

Even spark plugs that have been left in place WAY too long can often be removed with a little care and patience.

If you just put an air gun or a big wrench on them, yes, you will likely do some damage.

I’d run away from that place as quickly as possible.

These trucks are infamous for seized plugs, but they do have special tools out now designed for removing them. I would think the dealer would have them! I think $1000 is overblown.

They’re not gouging you at all. They’re simply giving you a worst case scenario because when it comes to removing spark plugs no one on Earth can possibly know if they’re going to come out without a fight or not.

We had an easily accessible Subaru into the shop once that needed plugs (just recently changed by a quick repair facility) and instead of the normal 10 minutes required it took me almost 4 hours.

Plug seizure is generally caused by overheating or allowing the plugs to remain in place for too many miles. Plugs should be replaced at around the 50k miles mark at most just to avoid any potential problems.

Do you have a Triton V8? Ford had a lot of problems with stripped out spark plug holes in these engines because one of the cylinders had only a few threads for the plug to grab. If you do some research on the net, you will see that many others have had problems requiring removal of the head to fix this.

Just to let you know, Ford has spark plugs listed as a 10 year or 100,000 mile replacement item. Your 2007 should not be anywhere near that yet. If you want to be pro-active, you can ask for the plugs to be pulled and anti-seize applied to the threads. But be prepared to pay for this service.

They don’t apply the anti-sieze at the factory? You’re essentially recommending the same $1000 job, without new plugs.

Any mechanic quoting a price based on his own potential incompetence doesn’t deserve the job. There are reputable Ford dealers and there are many that are not reputable. Yours is the latter. Find a good guy to service your car. Go to Angie’s list or just ask around. Don’t let this greedy creep touch your car.

Explain how a seized spark plug or a seized plug causing thread damage during removal is incompetence.

If a mechanic replaces a thermostat in a car and one of the 2 bolts holding the thermostat housing on snaps off during removal because it’s frozen would that also be incompetence?

Many factory spark plugs are NOT installed with anti-seize. I don’t know why. Maybe because they don’t want to spend an extra $0.20 per car. Also, the plugs are not scheduled to be removed until AFTER the warranty period. So, the risk of expensive damage is after they can be held to cover it, so who cares? It seems asinine to me, since steel plugs in an aluminum head will easily become galled, and a small dab of anti-seize can prevent that.

AFAIK, Ford does not.

This unfortunately is fairly common for the 3 valve Ford engines, the 5.4 3v in particular. Spark plugs in this engine have a different plug tip design (attached photo). In cases where significant mileage has accumulated, carbon and corrosion will get between the plug bore in the head and the plug tip causing it to seize to the head. When an attempt iis made to pull the plug the plug body comes out but the ground electrode stays in the head. Some cases all plugs come out easy in other cases 1-3 break. In really bad cases 8 will break off, this never should happen.

What can be done, experience has show that performing an upper engine decarbon procedure will often loosen the carbon enough to spin the plug out. Ford has there own TSB 08-7-6 for instructions how reduce the possibility of plug breakage, it is not 100% but it helps. It also shows how to remove the broken plug end.

Can technician work habits add to the problem, sure… You’ll see it once in a while with a mechanic using air tools to do a tuneup.

If the tips break there are multiple tools available to get the plug tips out of the head. The dealer obviously will have access to the Ford approved tool. MAC and Snap on also have there own version which works well if not better in my opinion over the Ford tool. Gets the work done in a fraction of the time. (considering 90-110 dollars an flat rate hour, any additional efficiency will help the wallet).

You may want to ask the dealer to perform an upper engine decarbon procedure… The can only cost a few bucks… Not the BG induction flush or any of that garbage, but a simple upper engine decarbon using the proper cleaner sprayed into the intake while the engine is running. It really does help, let the engine cool and loosen the plugs. If one breaks its not that big of a deal, the tech will use the tool, the tip comes out and off you go…The dealer is giving you worst case scenario with the 1000 dollar… The worst case scenarion should not include anything about removing or replacing the cyl head.

Ford has been making these engines since 1992. It’s used in Mustangs, Panthers and Pick-up trucks…Millions and millions have been made. The factory plugs are good for 100K miles before replacement is needed. It is very rare were we see a thread complaining about broken spark plugs. The hardest part is getting the $80 coils off and back on without damaging something. Perhaps the mechanics at this dealership need to put the air tools away when they are changing spark plugs… Or maybe the service writer was counting on 8 new coils too…The plugs cost about $4 each ($32) and any decent mechanic can change them in a hour ($150). So it’s $182 TOPS…Ahhh I see in the post above where in the 3 valve engines a weird extended plug must be used…Maybe by now they have improved the PLUG design…

Most long life plug today have an anti-seize plating on them. They should not get additional anti-seize paste on them.

No mechanic on Earth can ever know if whatever he’s attempting to loosen is going to come loose without a fight no matter what vehicle, part, or procedure is used. Sometimes things freeze or break and there’s just no way around it.

Plugs routinely break or seize on every vehicle made and have for decades often leading to thread repairs. Even something as simple as an oil change has no guarantee that the drain plug is going to come out without a fight.

As to plugs blowing out because of shallow threads I don’t even buy the shallow threads as being the reason for this. If shallow threads were the reason then plugs would be blowing out of lawnmowers, chainsaws, and my 2 60+ year old Harleys; all of which use shallow thread plugs.
Odds are the plugs were overtightened in a past life, either at the factory or by someone during a maintenance procedure.
The manual on my 4.6 Lincoln specifies 7 to 15 Ft. Lbs torque on spark plugs so one could take their pick on that barn door wide specification. Seven is fine, 15 is not IMO.

I just took my 04 f150 in for a tune up at my local mechanic shop that I use all the time, especially since its out of warranty. They broke the first plug they tried to remove and used the specialized tool to remove it. After that they had some luck with2 of them and then the worst happened—on the 4th plug they tried it too broke and they began using the tool to get it out when it broke off in the head and is now stuck. They have already removed the engine and head too and got it out, with the motor out now they have also noticed the excessive amount of carbon build up as well. Going to have to have a carbon cleaning done on top of the $1300.00 charge to remove the engine and remove the broken tool. My truck has 83000 miles on it and I wanted to get a leg up on the tune up because I had a while in drive sitting still stumble while idleing. So much for a cheap tune-up to take care of the problem…