Changed plugs on my 2019 f250 today and noticed after I was done that there are two types of plugs. Eight with blue stripes and a thin electrode and eight without the blue stripes and a fat electrode. Can't remember which ones were in which location but all the plugs I put in have the smaller thin electrode. Did I screw up and get the wrong plugs for half?

 

Someone must have changed just one plug per cylinder and used the wrong plugs.

Denny

 

I've owned the truck since it was new. So if it was a screw up it happened at the factory. Just wondering if the bottom cylinders require a different plug but everything I've checked said to use the SP526 for all of them.

one plug is marked CYFS 12NPG 9F and the other is 12F 9E but both have XP5363 stamped into the seating flange

 

One thing about it is they both look like they were burning clean but they also look like it was time to change them. I'm sure you will notice a difference.

Denny

 

I thought they'd be a little cleaner with only 50k on them. There were two that were worse and had a bunch of white corrosion around the boot and plug. All the used plugs gapped the same which surprised me. I started it up and ran it a few minutes and it seemed to run a bit smoother. Won't take it out on the road until I get the broken coil replaced in the morning, don't trust the tape job to hold the power cord on.

 

Mine were different as well.
I wish Ford would clarify why.

 

It's weird that they do that with no clarification. Oh well, my truck runs as smooth as can be with the new plugs and wires.

 

If you have the knack for searching (I do not) you can find a thread or two about a no start condition due to fouled lower plugs. Ford’s fix was to put hotter plugs in the lowers and run the oil level around the middle of the range on the dipstick as apposed to the top. It’s been a few years and that’s from memory so it’s probably not verbatim but you get the idea.

 

This is the only one I could find https://www.ford-trucks.com/forums/1...g-happned.html.

Denny

 

This is the only one I could find https://www.ford-trucks.com/forums/1...g-happned.html. nothing about two kinds of plugs.

Denny

 

Hello.
I just discovered this also on my '17 F-250, 130K, I bought it with 75K... Working on it last night, I was surprised to find two different type plugs in it... I can't find anything specific relating to two types of replacement plugs, I have 16 NGK iridium in stock so that's what going in... I have found some articles about plug brands, stating stick with Motorcraft... But honestly I think that's some up selling from Ford company?? But who knows, maybe it's a valid claim?? I have had good luck with NGK in everything I own with a gas engine... so I guess we will find out??.

 

I would have no concern about running NGK's. Let us know how you like them.

 

Ok, the reason why they are different is when they build the vehicle, they use two different kinds of plugs because the spark polarity is different or they felt they could go a bit cheaper with one of the plugs. The factory plugs would be "single platinum" This was common on waste spark system before COP (like my older vehicles below, where they had one coil fire two plugs but different polarity). That is probably how these twin coils work. $1-$2 over 100K vehicles is a bit of cash saved. The thicker one may have platinum on the electrode.

Also, that is likely an autolite plug- https://shop.advanceautoparts.com/p/...363/10500916-p
The crimp is a bit different from NGK.

AutoLite XP5363 IRIDIUM plug. They may have a slight variation for the application.

It is possible also they had two suppliers (Autolite and NGK for different years or production jobs). Both are probably fine.

 

I changed mine at 100k and didn't look at the old plugs. To tell you the truth, after changing plugs from above and below, I didn't have the slightest desire, so they went in the trash.
Somehow, it seems that it wouldn't make any difference, at least to me, because the COP is firing both at the same time, so either one or both are making it happen in the combustion chamber. The only thing that might matter is if there is a drastic difference between the plug's resistance, which might make the COP go bad sooner. I have replaced one COP that began arcing. The mechanic didn't say anything more, and that was when I had a ticking sound under the hood and I took it to him thinking about timing chains, which it turned out .that my problem was that COP and I needed to go back to 5 weight synthetic oil.

It's interesting that Ford would put two different plugs in. I put all the same in, and will the next time. I never thought about polarity. I don't believe it is polarity, just needs to be a more powerful or resilient COP to fire both plugs. The two plug design makes some sense to me about having a more complete combustion. If it is indeed something to do with polarity, it must be some garbage they did for the computer control of the engine, and I wouldn't have the slightest idea why. Some super duper computer engineer at Ford would need to explain that one, to me, using crayons and simple words.

 

I did mine recently too, they had 70-80k, not a picnic, some needed a bit more force than I was comfortable with, but they came out. All plugs were the same, they were changed by Ford in 2017. Some had nasty rust on shells, maybe eventually that corrodes thru. That is the longest I would suggest they go in, especially if there is road salt. Runs so good now I thought it stalled at a light. Also cleaned the MAF and TB. One plug was definitely broken. Also got new Ford wires, got a good deal on them.

And yes, older Fords came from the factory with different suffixed plugs (platinum on the tip or electrode). Before they switched to coil on plug, one coil pack controlled two plugs, and they were wired in with different polarity. Both plugs would fire at the same time.

The replacements were always the same "double platinum" plug. That is what a tech told me long ago, FWIW. Seems this setup also has one coil and 2 plugs...