BEST spark plugs for the 4.0 SOHC?


Which spark plugs work best in the 4.0 SOHC?


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6.2

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OEM plugs.

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6.2

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OEM motorcraft are the best plugs for these engines. Using something more expensive isn't better. It will be worse. Plenty of threads and info about this all over the internet.

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Mike Tonon

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Someone on here said Ford iridiums will go 100,000 miles, but stocks will really only go 10,000. I usually go at least 25,000 with stock Motorcraft plugs.
 

sgtsandman

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I vote OEM. I have never seen any difference or benefits going with anything other than the OEM spec plugs with any vehicle I've owned. Some were actually worse in some way or another.
 

adsm08

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Double platinum should go 100K, but I'd replace them at 75K.

Iridiums will go farther, how much farther I don't know.

I gotta ask though, what's with all the threads lately? It seems like most of this could have been handled in a single thread.
 

Mike Tonon

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Double platinum should go 100K, but I'd replace them at 75K.

Iridiums will go farther, how much farther I don't know.

I gotta ask though, what's with all the threads lately? It seems like most of this could have been handled in a single thread.
I just went to the dealer. They said the only plugs they have listed for this engine are platinum and were about $3.50 each. They recommend changing them after 100,000 miles.

All the threads because I thought I should separate everything into more specific categories. Should I have combined everything and posted in the general tech forum?
 

alwaysFlOoReD

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I think the separate threads are good for people searching in the future.
 

adsm08

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I think the separate threads are good for people searching in the future.
If the goal is simply knowledge for knowledge's sake, then yes. But when I see ten or twenty different threads from one user all pointing in one direction over the course of a week it makes me think "Is there a bigger question that isn't being asked".
 

Mike Tonon

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If the goal is simply knowledge for knowledge's sake, then yes. But when I see ten or twenty different threads from one user all pointing in one direction over the course of a week it makes me think "Is there a bigger question that isn't being asked".
Like what? I thought this was America! I didn’t know this was a socialist country! I thought this was America!
 

alwaysFlOoReD

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This site is based in America, but TRS is not a Democracy or a Republic. In some posts you are acting argumentative and being a general ______. I warned you once, this is your second. You won't get a third. In other posts you are asking and responding responsibly, please keep that up.
 
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sgtsandman

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I just went to the dealer. They said the only plugs they have listed for this engine are platinum and were about $3.50 each. They recommend changing them after 100,000 miles.

All the threads because I thought I should separate everything into more specific categories. Should I have combined everything and posted in the general tech forum?
That's pretty standard for platinum plugs. The OEM ones are mileage based as well but I can't remember what that is. It took me until last fall to hit that mileage with my 2011. Not a horribly short time period but it depends on what kind of mileage you expect to be driving your truck. Whatever you decide to go with, I strongly recommend you look up recommendations on how to change the plugs. Not getting at them at the right angle can make the job miserable. On the passenger side, I would highly recommend you go through the wheel well and pull the splash shield to do it. Coming in from the top is doable but a completely miserable experience with the back plug.
 

Mike Tonon

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Yea! I’ve done the back passenger plug through the wheel well.
 


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