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"Don't change thExpedition spark plugs yourself!" Why not?

2008 Expedition is running fine, 20 mpg!, but is past due to have the spark plugs changed.
I have always done the spark plugs on all of my vehicles. Why not this one?

Thank you.

Do a web search for “Ford Triton 3-valve spark plugs” and you’ll have a wealth of reading on spark plug issues on these engines.

Some helpful (but counter-intuitive) hints:
Have a fuel injection cleaning/engine de-carbon service done prior to spark plug removal.
Remove the spark plugs when the engine is hot, at operating temperature.
Use an air impact wrench if at all possible. If you do it by hand, move fast and keep turning the spark plug out. Don’t stop turning no matter how hard it feels.

Click on the link for Ford TSB 08-7-6, spark plug removal instructions. Check the build date on your engine, not all 2008’s are affected.

You might want to research Ford spark plug removal tools in advance in case you break a plug. There are many, many versions available. That also should tell you how common the problem is. It’s not that you need to buy any in advance but should the worst happen you have an idea of what you can do to fix it.

“Use an air impact wrench if at all possible. If you do it by hand, move fast and keep turning the spark plug out. Don’t stop turning no matter how hard it feels.”

Wow, I’m not doubting you, because I’m assuming you have some experience with these engines, and I do not, but this sounds like advice for someone that wants to destroy the threads in the cylinder head. On any other engine, this sounds like what not to do.

Definitely don’t use an impact wrench to reinstall them…

I’m no expert Oblivion and I have always practiced what you do but having read about these particular issues the most important thing is to get them out. If you stop they can seize and likely break off. Easier to fix threads than get broken plug out. I’d follow all the recommended precautions given here before attempting and then make sure they come out intact if at all possible.

this is Ford’s better idea about how to make a spark plug . champion has a one piece plug that is the way i would go but i would price a shop to do this job becouse the tool costs about $200.00. becouse they say plugs can last 100k miles i would still change them about 50k.

Letting anyone near a spark plug with an impact gun has ‘disaster’ written all over it.
What were those bonehead designers thinking?

This may help… I honestly had NO IDEA this was such a big issue… So I learned something today !!

How horrible.
Wonderful Ford. Cause the creation and manufacture of yet another component which is likely morexpen$ive, and cause major problems getting it out.
If the dealer breaks the spark plug, do I pay more for them to extract it?
Like we have $350 to replace SPARK PLUGS!

OK, let me explain. The bonehead designers were trying to come up with a better spark plug with the spark located in the center of the combustion chamber. The spark plug threads actually protrude into the combution chamber. They get carbon buildup as much as the top of the piston and the inside of the cylinder head, and that’s what causes the plugs to seize and break upon removal. Doing a MotorVac or other such service helps to loosen and soften the carbon stuck on the threads. Working on a warm engine means the carbon is softer and more likely to give. And the rattling action of the 3/8 impact keeps the plug moving so it doesn’t get stuck in the head.

The Ford service bulletin assumes you can break the plug free enough that pouring carb cleaner down the well will penetrate all the threads. It’s time consuming and messy, and I’ve seen guys still end up with a broken plug. I have yet to buy the extractor set, since I’ve not broken any plugs.

Like we have $350 to replace SPARK PLUGS!
Please tell me you didn't buy a $40,000 SUV and think it would be cheap to maintain.
If the dealer breaks the spark plug, do I pay more for them to extract it?
You need to ask them that before you give them the job. Normally, I would expect them to extract it at their expense and repair any damage free of charge, but if this is a known issue, all bets are off.

I agree with those that feel this design is unrealistic and should have been rethought before unleashing it on the public. Expeditions aren’t cheap, but they’re not uber luxury vehicles. They’re work vehicles or something for a large family…especially if the family has a boat. IMHO one should be able to expect maintenance to be reasonably normal in cost and aggrivation for these vehicles. They’re not Bugattis.

However, as much as I feel it should not happen, I suspect that as direct injection systems take hold we’ll be discovering more plugs (and injectors) that’ll take a Houdini to replace.

If it was a Bugatti, I would expect a spark plug job to cost at least $1,350.

It may not be a luxury vehicle, but at that price point, you can’t expect a vehicle like that to be as cheap to maintain as an Escape, which is half the purchase price.

Unfortunately, Ford isn’t able to roll-out its huge gas hogs in Europe like it did the Focus, so we Americans get to be the guinea pigs for the Expedition.

I imagine Ford was probably trying to eek out a few extra MPGs from this engine. If this design is able to do that, you should be able to find the $350 you pay for a spark plug job in the fuel savings. The OP should be glad he is able to get the 20 MPG he says he is getting and use the money he’s saved on fuel to get this job done right. It sounds like a fair trade-off to me.

Clearly our perspectives on this subject are different. I consider that design to be extremely poor for the intended market segment. I would definitely expect the cost of ownership to be considerably higher than a Focus, but that plug installation is very poorly thought out.

You may, however, be right about our being used as Guinea Pigs for the Expedition.

It may not be a luxury vehicle, but at that price point, you can't expect a vehicle like that to be as cheap to maintain as an Escape, which is half the purchase price.

But what’s going to happen when the Escape gets a direct injection system? Is direct injection the future?

I have to think that there’s a BETTER design. It could be that the direct injection was introduced at the last minute and then the sparkplug design was rushed to to design.

Not having seen the design myself, I must agree with both of you. I just hope, for Ford’s sake, there is a logical reason for it, like fuel savings. If that is the case, it may be a bad mechanical design, but a good economic choice.

To me it smells like the time GM took a gas engine and turned it into a diesel.

“I have to think that there’s a BETTER design.”

As these systems are used and found to be unsatisfactory, manufacturers will devise other designs to accomplish their goals. Eventually, one or more will work well, and everyone will conform. Or at least find something similar that doesn’t infringe on existing patents if they exist.

What a nightmare. Yet another reason, IMHO, that no spark plug should be left in a head for more than 50k miles.