Motorcraft SP-542 plug superseded by SP-578? - New Plug Installation DIY

[boostededge]

My owners manual says SP-542, but when I went to the dealer they tell me these plugs are superseded by the SP-578 plug & they dont have any information as far as heat range or material. A couple of googles also really didnt produce any factual data about this new plug. Does anyone know what the difference is and which one is optimal? Other than "tuners recommend 542" once all those plugs are gone we will be stuck with the 578's good or bad.

[1004ron]

On 7/29/2019 at 1:25 PM, boostededge said:

My owners manual says SP-542, but when I went to the dealer they tell me these plugs are superseded by the SP-578 plug & they dont have any information as far as heat range or material. A couple of googles also really didnt produce any factual data about this new plug. Does anyone know what the difference is and which one is optimal? Other than "tuners recommend 542" once all those plugs are gone we will be stuck with the 578's good or bad.

Looking at changing my plugs soon, and have the same question.

[1004ron]

Anyone bought spark plugs recently and does anyone have any feedback on the new Motocraft SP-578?

 

I'm looking to buy soon and was also looking at the latest NGK 95605 Ruthenium HX.

 

Also, any seals and gaskets needed?

 

 

 

 

 

Edited October 28, 2020 by 1004ron

[WWWPerfA_ZN0W]

You may want to get the plugs from ford performance instead.

 

These may work

https://performanceparts.ford.com/part/M-12405-35T

 

One discussion

https://www.ecoboostperformanceforum.com/index.php/topic,10409

https://www.ecoboostperformanceforum.com/index.php/topic,10388

 

Loss of spark advance and slower 1/4 miles times among the reported issues.

Edited October 29, 2020 by WWWPerfA_ZN0W

[1004ron]

39 minutes ago, WWWPerfA_ZN0W said:

You may want to get the plugs from ford performance instead.

 

These may work

https://performanceparts.ford.com/part/M-12405-35T

 

One discussion

https://www.ecoboostperformanceforum.com/index.php/topic,10409

https://www.ecoboostperformanceforum.com/index.php/topic,10388

 

Loss of spark advance and slower 1/4 miles times among the reported issues.

Thanks for that.

 

Way better deal here: https://www.levittownfordparts.com/sku/m-12405-35t.html

PART NUMBER: M-12405-35T

 

The web site says they're not for the Edge, but are correct for the F-150 without detailing which F-150 engine.

 

Not much details available for those plugs and not sure if they're better than the NGK 95605 Ruthenium HX

[todd92]

Autolite XP5362.  Motorcraft=Autolite.  This is for the 2.7.

XP5863 for the 2.0.

XP5363 for the 3.5.

[onyxbfly]

6 hours ago, 1004ron said:

Thanks for that.

 

Way better deal here: https://www.levittownfordparts.com/sku/m-12405-35t.html

PART NUMBER: M-12405-35T

 

The web site says they're not for the Edge, but are correct for the F-150 without detailing which F-150 engine.

 

Not much details available for those plugs and not sure if they're better than the NGK 95605 Ruthenium HX

 

Good enough for the worlds fastest edge..... good enough for mine!

[1004ron]

On 10/29/2020 at 12:20 PM, WWWPerfA_ZN0W said:

You may want to get the plugs from ford performance instead.

 

These may work

https://performanceparts.ford.com/part/M-12405-35T

 

One discussion

https://www.ecoboostperformanceforum.com/index.php/topic,10409

https://www.ecoboostperformanceforum.com/index.php/topic,10388

 

Loss of spark advance and slower 1/4 miles times among the reported issues.

Response received from https://www.levittownfordparts.com

 

Quote

These are not recommended for the Edge.

 

Fits:

2011-2019 F-150 3.5L EcoBoost
2017-2019 F-150 Raptor 3.5L EcoBoost
2010-2019 Taurus SHO 3.5L EcoBoost
2010-2019 Flex 3.5L EcoBoost

 

[Perblue]

14 hours ago, 1004ron said:

Response received from https://www.levittownfordparts.com

 

 

 

They may not be recommended but the 3.5L eco raptor guys were running the sp542s for a cold plug. The sp578s are now their recommended stock plug, both plugs that Sport/ST people use and are actually a hotter plug than the sp578.

 

The M-12405-35T Is now actually the recommended replacement for the sp542s for them wanting a cold plug so it should be fine otherwise the other plugs should've caused issues also.

[WWWPerfA_ZN0W]

And availability for these plugs may be longer lived than the SP542s, but if you are an avid OCD plug changer, wouldn't be a bad idea to cough up some dough for a few sets at once.

[1004ron]

Today I decided to install the NGK 95605 Ruthenium HX plugs that I bought recently, .....not because they needed changing at 62K miles, but because I'm a tinkerer and and having the new plugs gave me itchy fingers.

Plugs bought from Rockauto.com for $53 shipped.

 

The original plugs would easily be good for 100+K  miles and all their gaps were a snug 32 thou.

 

With the plugs out looking down on top of the pistons they are so clean I could read the numbers on their crowns - my Edge only gets Costco Top Tier premium.

 

The job took just over 4 hours, which includes a trip to Lowe's to get additional 1/2" drive socket extensions.

 

The rear plugs are a challenge - I did not remove the air tube coming up from the rear turbo and it would be easier with that out of the way. I removed the flex rubber tube connecting it to the air filter housing and pulled it to left and right to get the two plugs that it obstructs.

 

For the rear plugs you need to secure the plug socket to a 5" extension and once inserted down the tube and onto the plug then place the 2" or 3" extension onto that, and then a ratchet with pivoting head - this is due to the restricted head clearance.

 

Added a little dielectric grease to the rubber ignition coils tubes to prevent them sticking to the plug porcelain part of the plug.

 

I'm not a good technical author, so feel free to ask questions if you plan on this DIY.

 

Excerpt from the service manual.

Ignition Coil-On-Plug.pdf

 

No anti-seize used on the plug threads as per the manufacturers recommendation.

https://ngksparkplugs.com/en/resources/5-things-you-should-know-about-spark-plugs

 

 

 

 

 

 

 

 

Edited November 7, 2020 by 1004ron

[handfiler]

47 minutes ago, 1004ron said:

I'm not a good technical author, so feel free to ask questions if you plan on this DIY.

 

Excerpt from the service manual.

Ignition Coil-On-Plug.pdf

 

No anti-seize used on the plug threads as per the manufacturers recommendation.

https://ngksparkplugs.com/en/resources/5-things-you-should-know-about-spark-plugs

 

The pictures and links more than make up for it. A salute to tinkerers everywhere! 🍻

[WWWPerfA_ZN0W]

Did you gap the old/new plugs? Ecoboost plugs don't like much gap growth before starting to show signs of wear, compared to those for NA engines.

[1004ron]

12 hours ago, WWWPerfA_ZN0W said:

Did you gap the old/new plugs? Ecoboost plugs don't like much gap growth before starting to show signs of wear, compared to those for NA engines.

The old plugs gap was still spot on at 32 thou, and I checked the new NGK plugs and they were closer to 30 thou and I left them at that - no gapping done.

 

BTW, I also changed the plugs  in my wife's NA Mustang 3.7L V6 this weekend using the NGK Ruthenium HX plugs. It has 65K miles on the clock and I'd say that it was due for replacement plugs due the gap growth which is 50 thou to start with new - although it requires removal of the intake air plenum its a much easier job.

Edited November 8, 2020 by 1004ron

[WWWPerfA_ZN0W]

Your Edge is running very well, keep up the good work!

[Tlaner30]

On 11/7/2020 at 2:36 PM, 1004ron said:

Today I decided to install the NGK 95605 Ruthenium HX plugs

What torque did you tighten the plugs to?

Edited May 10 by 1004ron
No need to quote everything !

[1004ron]

4 hours ago, Tlaner30 said:

What torque did you tighten the plugs to?

I don't use a torque wrench on spark plugs, but would advise following the tightening instructions on the NGK packaging, which is specific the the plug and its seal arrangement.

 

The top image is for the NGK 95605 Ruthenium HX plugs

Edited May 10 by 1004ron
Added image

[Xtra]

On 11/7/2020 at 11:36 AM, 1004ron said:

Today I decided to install the NGK 95605 Ruthenium HX plugs that I bought recently, .....not because they needed changing at 62K miles, but because I'm a tinkerer and and having the new plugs gave me itchy fingers.

Plugs bought from Rockauto.com for $53 shipped.

 

 Have you noticed any difference in the Edge or Mustang's power, milage, smoothness at idle, cruising or acceleration after installing the new NGK Ruthenium HX plugs ? 

Nice job with the photos, explanation of a new product and the tools needed.  

Edited May 13 by Xtra

[1004ron]

24 minutes ago, Xtra said:

 

 Have you noticed any difference in the Edge or Mustang's power, milage, smoothness at idle, cruising or acceleration after installing the new NGK Ruthenium HX plugs ? 

Nice job with the photos, explanation of a new product and the tools needed.  

Thanks.

 

No discernible difference, but that can be expected considering the original plugs were still very good.

Bear in mind that I baby the car, never once been above 5K RPM.

 

I installed the NGK's at 62,300 miles and I'm at 79,500 miles and still going like it did when I took delivery of it in March 2017.

 

I bought my Edge while I was abroad, never sat in an Edge let alone test drive one, and the dealership's courtesy driver picked my wife and I up at the airport with all our baggage.

I was familiar with the dealership because I had the company car serviced there for a few years.