Another Spark Plug Thread

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slypher25aussie

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Going a bit cross eyed trying to figure out which plugs to get. ACDelco has a nice rebate right now, but it looks like they don't make the original iridium plugs for my truck anymore. The manual says 41-974, but when searching that, I get cross referenced to 41-162, but I also see people talking about 41-110... so I'm just plain confused now. Also, are double platinum plugs worth it over regular platinum?
 

drakon543

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if you want the iridium just get the ngk one its a great spark plug.
 

Fless

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I used AC Delco 41-962 double platinum - as recommended by GM - with no issues. Runs smooth.
 

Fless

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My '04 5.3 came with 41-985s. I inquired directly to ACDelco about the unavailability of those, and this is the response I received:


Regarding your inquiry for spark plug for VIN [cut], we show the correct part number to be 41-962. The 41-985 are discontinued and they do show to supersede to 12621258 which is not available and they are no longer recommended for your vehicle. The engineers have made the change to the new spark plug.

If you have any other questions, please feel free to contact our experts at the ACDelco support center by dialing 1-800-ACDELCO (223-3526).

We appreciate your business.

Regards,

ACDelco Internet Response Team

EDIT: 2008 TSB here: https://f01.justanswer.com/edhunt0r/88cbc3c3-4ce4-40b9-9e0e-5749f0bcc19e_Avalanche+plug+gap.pdf
 
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slypher25aussie

slypher25aussie

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My '04 5.3 came with 41-985s. I inquired directly to ACDelco about the unavailability of those, and this is the response I received:


Regarding your inquiry for spark plug for VIN [cut], we show the correct part number to be 41-962. The 41-985 are discontinued and they do show to supersede to 12621258 which is not available and they are no longer recommended for your vehicle. The engineers have made the change to the new spark plug.

If you have any other questions, please feel free to contact our experts at the ACDelco support center by dialing 1-800-ACDELCO (223-3526).

We appreciate your business.

Regards,

ACDelco Internet Response Team

EDIT: 2008 TSB here: https://f01.justanswer.com/edhunt0r/88cbc3c3-4ce4-40b9-9e0e-5749f0bcc19e_Avalanche+plug+gap.pdf

Thanks for that. Seems like ACDelco/GM engineers can't make up their mind about which plugs are best lol. I think I'm going to go with the 41-110 iridium plugs. After rebate, I can get all 8 for about $25.
 

mattbta

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I've put the 41-110 in mine twice now and the yearly rebate Delco runs is nice. Once due to original mileage, the other because I was swapping heads.

They seem to do fine, but contemplating going with a non iridium or platinum one just for grins. Truck doesn't get driven enough that changing every so often is a big deal. #8 isn't nearly as hard as my old f-bodies. I used to run NGK TR6's or TR55's just because they were colder. Haven't figured out what I'll go with next for certain.
 
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slypher25aussie

slypher25aussie

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I've put the 41-110 in mine twice now and the yearly rebate Delco runs is nice. Once due to original mileage, the other because I was swapping heads.

They seem to do fine, but contemplating going with a non iridium or platinum one just for grins. Truck doesn't get driven enough that changing every so often is a big deal. #8 isn't nearly as hard as my old f-bodies. I used to run NGK TR6's or TR55's just because they were colder. Haven't figured out what I'll go with next for certain.

Curious... why are you considering switching from the iridiums?
 

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