Spark plug debate - 2013 5.3 LMG

[DaveO9]

In the middle of doing plugs and wires, with PS front fender skirt removed due to starter replacement. So vehicle is down and want to get it back up, but there's been a delay....

I first ordered from Amazon: 8 AC-Delco 41-962 platinum plugs and 9748HH wire kit which includes the plug boot metal heat shields. I have this in my possession now, and it all looks legit. But shortly after ordering I did further research and most, but not all, recommendations were to stick with OEM iridium plugs, as a perf degradation may occur with platinum. (longevity not a big issue, it will take me a long time to wear out either of those) so I then ended up finding the same wire kit (minus the heat shields) and (8) 41-162 iridium plugs for about the same price, $150, on RockAuto. My thought was I'd send the Amazon stuff back, since it's pretty easy to do returns.

Well now I have the Amazon stuff, but not the RA stuff, even though they were supposed to arrive on the same day. (Not RA's fault, Fed Ex - Grrrr)

I will probably just wait patiently for the RA order to arrive at end of this week, but wanted to check in here. What's the vote: wait and go with the Iridium plugs or just install the platinum now? Would I notice any performance or MPG loss with platinum? I know everyone loves debating spark plugs.

 

[OR VietVet]

Stick with what came in it. Have some patience.

 

[swathdiver]

Well, GM offers it and it works so you could use them since you have them. I prefer the OE stuff because I really don't know any better! Decades ago I played around with spark plugs and knew which ones squeezed the last drop of power from the motor and at what cost as I used to change them between passes at the drag strip.

 

[kbuskill]

I would wait on the RA plugs.

There are a ton of very convincing knock off plugs on the market.

I bought a set of "iridium" AC Delco plugs from either Amazon or Ebay, can't remember which and when they arrived they looked absolutely legit comparing them to the originals i pulled out. I drove on them for a while and decided I wanted to try something else so I bought the Ruthenium plugs from RA. When I pulled the "iridium AC Delco" plugs out they were so worn down it was shocking.

I have pulled many sets of Iridium plugs at 100k+ miles and they could have been cleaned and reinstalled without any issue. These knock offs were worn down to the porcelain.



Knock off Delco on the right and New NGK Ruthenium plug on the left.

I don't know the exact mileage but I know it was somewhere between 25k and 50k miles on these plugs. So roughly half or less of the recommended service life of Iridium plugs.

 

[donjetman]

In the middle of doing plugs and wires, with PS front fender skirt removed due to starter replacement. So vehicle is down and want to get it back up, but there's been a delay....

I first ordered from Amazon: 8 AC-Delco 41-962 platinum plugs and 9748HH wire kit which includes the plug boot metal heat shields. I have this in my possession now, and it all looks legit. But shortly after ordering I did further research and most, but not all, recommendations were to stick with OEM iridium plugs, as a perf degradation may occur with platinum. (longevity not a big issue, it will take me a long time to wear out either of those) so I then ended up finding the same wire kit (minus the heat shields) and (8) 41-162 iridium plugs for about the same price, $150, on RockAuto. My thought was I'd send the Amazon stuff back, since it's pretty easy to do returns.

Well now I have the Amazon stuff, but not the RA stuff, even though they were supposed to arrive on the same day. (Not RA's fault, Fed Ex - Grrrr)

I will probably just wait patiently for the RA order to arrive at end of this week, but wanted to check in here. What's the vote: wait and go with the Iridium plugs or just install the platinum now? Would I notice any performance or MPG loss with platinum? I know everyone loves debating spark plugs.

I installed AC Delco 41-962 plugs 2 yrs 20k miles ago and AC Delco 9748RR wire set 5 yrs and 60k miles ago, both from amazon, no issues.

 

[Geotrash]

I would wait on the RA plugs.

There are a ton of very convincing knock off plugs on the market.

I bought a set of "iridium" AC Delco plugs from either Amazon or Ebay, can't remember which and when they arrived they looked absolutely legit comparing them to the originals i pulled out. I drove on them for a while and decided I wanted to try something else so I bought the Ruthenium plugs from RA. When I pulled the "iridium AC Delco" plugs out they were so worn down it was shocking.

I have pulled many sets of Iridium plugs at 100k+ miles and they could have been cleaned and reinstalled without any issue. These knock offs were worn down to the porcelain.

View attachment 411641View attachment 411642

Knock off Delco on the right and New NGK Ruthenium plug on the left.

I don't know the exact mileage but I know it was somewhere between 25k and 50k miles on these plugs. So roughly half or less of the recommended service life of Iridium plugs.

I have a friend who owns a fluid seal factory in India, and has for many years. They engineer their products properly and manufacture them under strict quality control. So much so, they've developed a stellar reputation over the years and are an OEM supplier to Tata Motors, Mahindra and others. But over the past several years, the companies faking his company's products and distributing them have gotten more and more sophisticated, to the point that they're sometimes showing up in the downstream supply chain to established retailers and resellers. The fake packaging even has a nearly identical holographic seal. They've had to implement several new measures including regular minor changes to their packaging and holographic seals, a serial number tracking system with scannable QR codes on the boxes, etc etc.

 

[kbuskill]

I have a friend who owns a fluid seal factory in India, and has for many years. They engineer their products properly and manufacture them under strict quality control. So much so, they've developed a stellar reputation over the years and are an OEM supplier to Tata Motors, Mahindra and others. But over the past several years, the companies faking his company's products and distributing them have gotten more and more sophisticated, to the point that they're sometimes showing up in the downstream supply chain to established retailers and resellers. The fake packaging even has a nearly identical holographic seal. They've had to implement several new measures including regular minor changes to their packaging and holographic seals, a serial number tracking system with scannable QR codes on the boxes, etc etc.

It never ceases to amaze me. You wouldn't think the margin for profit would be great enough to be worth fooling with for a couple dollars difference in price. The only answer is in volume so that should tell you how wide spread the issue is.

 

[Geotrash]

It never ceases to amaze me. You wouldn't think the margin for profit would be great enough to be worth fooling with for a couple dollars difference in price. The only answer is in volume so that should tell you how wide spread the issue is.

Yes. And the R&D necessary to design a seal for a specific OEM application is prohibitively expensive. The precise design of the lip on the seal, the chemistry of the material, the tension of the spring that surround the seal lip all have to be precisely engineered for the application. So when you fake it, it may look identical to the eye but it's definitely not identical and won't last after install.

 

[Sparksalot]

I would wait on the RA plugs.

There are a ton of very convincing knock off plugs on the market.

I bought a set of "iridium" AC Delco plugs from either Amazon or Ebay, can't remember which and when they arrived they looked absolutely legit comparing them to the originals i pulled out. I drove on them for a while and decided I wanted to try something else so I bought the Ruthenium plugs from RA. When I pulled the "iridium AC Delco" plugs out they were so worn down it was shocking.

I have pulled many sets of Iridium plugs at 100k+ miles and they could have been cleaned and reinstalled without any issue. These knock offs were worn down to the porcelain.

View attachment 411641View attachment 411642

Knock off Delco on the right and New NGK Ruthenium plug on the left.

I don't know the exact mileage but I know it was somewhere between 25k and 50k miles on these plugs. So roughly half or less of the recommended service life of Iridium plugs.

I'm getting to the point I don't trust many auto parts, and some other on Amazon to not be counterfeit. Some items it doesn't matter, but plugs and other items I want to last a while, I go to RA.

 

[Geotrash]

I'm getting to the point I don't trust many auto parts, and some other on Amazon to not be counterfeit. Some items it doesn't matter, but plugs and other items I want to last a while, I go to RA.

Me too. And the "ACDelco Store" on Amazon isn't necessarily the seller you're buying the parts from, even though it says "Visit the ACDelco store" in the listing. Also when it says sold by Amazon, there is no way to know the lineage of the part anyway. We are entering an age where the integrity of a company's supply chain will be a decisive differentiator.