NGK Ruthenium vs AC Delco Iridium spark plugs for 5.3?

[Grumpy Bear]

 

3 hours ago, Hazem A said:

I was under the impression that NGK Ruthenium advertised as a High Ignitability plug would save significant gas milage especially with its high durability or long service life, so i bought a set of 8 pcs from rockauto along with a new set of GM genuine wires for my 2015 Seirra Denali 6.2l

 

NGK 90220 Ruthenium HX High Ignitability; Pre-Set Gap: 0.044" Info   

 

Few days after replacement, I started to have random misfire code P0300. Spent few days trying to diagnose the problem and the misfire was eliminated after reverting back to ACDelco 41-114 OEM plugs except for Cylinder #. 8. Apparently, the injectors were affected and now i have to bear nearly $1000 USD to replace all 8 injectors, fuel lines and fuel pipes. I regret going for aftermarket parts when it comes to essential engine components and will never do it again.

 

The conclusion:

I wouldn't recommend going for NGK Ruthenium plugs under any circumstances. Genuine Iridium OEM plugs with 0.04" design gap offer excellent service life without an issue.

 

I put a set of Ruthenium plugs in Dizzy the oil eater. Work like a charm.

 

Killing an injector? Rubbish. I wore boots today and got a flat tire. My boots didn't cause a flat tire. 

 

ACDelco doesn't make plugs. NGK makes plugs with ACDelco labels. They don't make better parts for their other labels than their own. Actually, the Ruthenium plug is the only plug in the line with an EXACT resistance. 5K Ohms. All others are a range, 2 to 7K.

 

Going back about 50 years 5K miles was plug change time when electrodes were steel. It is the use of precious metals that permits long life under harsher conditions. Little to no erosion.  

 

 

[Grumpy Bear]

Speaking of 'back in the day". I didn't change plugs at 5K. I pulled them, cleaned them. Filed the electrodes sharp again, re-gaped them and ran them another 5K or until they missed. Rinse and repeat until there was nothing left to clean gap. They cost about a quarter then. 

[newdude]

4 hours ago, Hazem A said:

I was under the impression that NGK Ruthenium advertised as a High Ignitability plug would save significant gas milage especially with its high durability or long service life, so i bought a set of 8 pcs from rockauto along with a new set of GM genuine wires for my 2015 Seirra Denali 6.2l

 

NGK 90220 Ruthenium HX High Ignitability; Pre-Set Gap: 0.044" Info   

 

Few days after replacement, I started to have random misfire code P0300. Spent few days trying to diagnose the problem and the misfire was eliminated after reverting back to ACDelco 41-114 OEM plugs except for Cylinder #. 8. Apparently, the injectors were affected and now i have to bear nearly $1000 USD to replace all 8 injectors, fuel lines and fuel pipes. I regret going for aftermarket parts when it comes to essential engine components and will never do it again.

 

The conclusion:

I wouldn't recommend going for NGK Ruthenium plugs under any circumstances. Genuine Iridium OEM plugs with 0.04" design gap offer excellent service life without an issue.

 

 

 

Injectors are a known failure point on these engines and its quite common.  The plugs are unlikely the culprit here.  

[mikeyk101]

5 hours ago, Hazem A said:

Few days after replacement, I started to have random misfire code P0300. Spent few days trying to diagnose the problem and the misfire was eliminated after reverting back to ACDelco 41-114 OEM plugs except for Cylinder #. 8. Apparently, the injectors were affected and now i have to bear nearly $1000 USD to replace all 8 injectors, fuel lines and fuel pipes. I regret going for aftermarket parts when it comes to essential engine components and will never do it again.

 

I'm just curious if only 1 cylinder is having a problem with a fuel injector, why do all 8 have to be replaced? I know I was having a problem last year with misfires and it was determined that the fuel injector on cylinder 1 (IIRC) was bad and stuck open. Only that injector was replaced by the dealer under service plan and haven't had a problem since. I would have preferred all to be replaced for good measure or at least all the ones on that side but service plan only allowed the defective one to be replaced and so far so good.

 

But back to the discussion of OEM vs Aftermarket, I will sometimes use some OEM and sometimes aftermarket, it just depends on a lot of variables... what is being replaced or upgraded, cost, availability, etc... For spark plugs, I replaced mine last year but stuck with the OEM and got a healthy rebate. Both O'Reilly and AC Delco had rebates and I think it only cost just over $2 a plug. The OEM had served me well so no reason to change. Same with my coolant thermostat. Old one went bad and I tried an aftermarket replacement but that lasted only maybe a couple months. I replaced that one with OEM but lower temp and so far so good. Oil is always the OEM recommended but only because it gets done by dealer and that's what they use. It doesn't cost much more for dealer to do it than if I did it myself so I treat myself on that. But with shocks and struts, OEM left a lot to desire so aftermarket was the way I went there. I did go with Rancho for front struts but bought the QuickLift ones and put Bilstein 4600 shocks in rear.  Many repairs, I try to tackle myself. As vehicles age, OEM parts start to dwindle and then the aftermarket becomes very valuable. My 2016 is still new enough where parts are still available so mostly OEM is my choice for now 

[sk]

On 7/19/2023 at 6:23 AM, Hazem A said:

I was under the impression that NGK Ruthenium advertised as a High Ignitability plug would save significant gas milage especially with its high durability or long service life, so i bought a set of 8 pcs from rockauto along with a new set of GM genuine wires for my 2015 Seirra Denali 6.2l

 

NGK 90220 Ruthenium HX High Ignitability; Pre-Set Gap: 0.044" Info   

 

Few days after replacement, I started to have random misfire code P0300. Spent few days trying to diagnose the problem and the misfire was eliminated after reverting back to ACDelco 41-114 OEM plugs except for Cylinder #. 8. Apparently, the injectors were affected and now i have to bear nearly $1000 USD to replace all 8 injectors, fuel lines and fuel pipes. I regret going for aftermarket parts when it comes to essential engine components and will never do it again.

 

The conclusion:

I wouldn't recommend going for NGK Ruthenium plugs under any circumstances. Genuine Iridium OEM plugs with 0.04" design gap offer excellent service life without an issue.

 

I have been running Ruthenium plugs in my 2015 5.3L for over 30,000 miles now.  Noticed improved fuel mileage, smoother idle, and cleaner burning right after I put them in.  No problems at all so far, and I just checked them recently and they are very clean for their age.  Will probably replace with the same thing in a few more thousand miles.

 

Also as others above said, guess who makes the ACDelco-branded plugs?  Yep, NGK.  They are built to specs that GM lays out, which aren't always based on the best for the life of the engine (they usually are spec'd to meet some government requirements).  That's not to say the OEM plugs are junk, they will work fine for the application.  But paying more for the Ruthenium ones will get you some improvement, it's just up to personal preference.

Edited July 20, 2023 by sk

[16LT4]

GM somewhat quietly raised the warranty on injectors to 10 years/150k miles.  I had one replaced earlier this year; I diagnosed a weeping HPFP via the GM test procedure, replaced it (scraping the intake valves clean while the intake was off), but still couldn't cure the -7% fuel trims and <1% fuel dilution.  Knowing the  recall, the dealer diagnosed a faulty injector.  I had them replace the other 7 while they were in there, because if one failed, the rest aren't far behind, and I refuse to play "whack a mole."  I arranged a little bit of price discount, and it only cost an extra $300 for them to do all 8 (with parts/labor warranty) vs. me doing it at my cost.  As I'd already done two timing chains in the previous few months, I had them do the weeping front cover seal and oil cooler line at the same time.

[Delta Tango]

I just bought 8 x 14-114 AC plugs for my 2021 5.3 litre GMC Sierra. I see there are different letters/numbers printed on the flats of the hex for spark plug socket R and R.

I hope these are not "cal codes" and I hope this is not a dealer notation to enter via their computers after installation?

[Grumpy Bear]

3 hours ago, Delta Tango said:

I hope these are not "cal codes" and I hope this is not a dealer notation to enter via their computers after installation?

 

Nope

[Delta Tango]

Just to let you folks know I'm working on this spark plug R and R as we speak.

However much money The General pays these engineering people to make things difficult (even for HD diesel mechanics) to do maintenance here at the home base......it's working!

[Delta Tango]

Driver's side bank done=2.0 hours.

 

Some blood shed. Minor.

[Grumpy Bear]

5 minutes ago, Delta Tango said:

Driver's side bank done=2.0 hours.

 

Some blood shed. Minor.

 

Guy could have a 50K square foot home. The sump pump you need to work on is in the darkest corner of the basement hidden behind whatever and under the lowest shelf they could build. Keep plugging away. 

[Delta Tango]

Total time for air cleaner base and assorted giblets R and R was a tad over an hour. Lost one washer and wrecked a zap strap holder (small).

 

Passenger side, here I come.

[Delta Tango]

It's important to take water breaks and even take a phone call or two.

 

Keeps the mind clear, and the language decent.....

[Delta Tango]

Passenger side bank DONE!

 

Now for the ever important yet recently neglected road test.

[Delta Tango]

Road test completed.

Took unit on slight hill for a wee bit of a load.

No CEL’s!

I’m happy with the outcome but anyone reading this and is used to changing plugs on their 1972 GMC w/inline 6… stay away!

This was not for the faint of heart, there’s too much in the way and that takes time and effort.

I rate my project as 40% talent and 60% luck!