Do these spark plugs look normal?

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Cryptothedog

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I just replaced the plugs on my 2015 Suburban. I'm assuming they have never been changed. It has 161,000 miles on it. The old ones look like this. Is this normal or is there something wrong with my engine? (Yes i know there are only 5...I thre w the other ones away before i took the pic. They look the same though)20230415_173224.jpg
 

Sam Harris

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I’m no expert plug reader, but for having a LOT of miles on them, I’d say they look as expected. Seems like there’s a bit of some buildup of crud around the insulators, but don’t see anything really bad. The gaps look possibly a bit uneven, but again, with that many miles, not surprising. How’s she running after the swap?
 
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Cryptothedog

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Good to hear. Thanks for the feedback. It's running great! It was running fine before though. I just got the truck about 10k miles ago and figured they probably hadn't been changed and just started getting a misfire on cylinder 7. so I figured I would change them.
 

Sam Harris

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Good to hear. Thanks for the feedback. It's running great! It was running fine before though. I just got the truck about 10k miles ago and figured they probably hadn't been changed and just started getting a misfire on cylinder 7. so I figured I would change them.
Nice! What other maintenance items do you have planned? Please also post pics of the truck. We like pics.
 
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Cryptothedog

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Well I changed the Transmission fluid already through the cooler lines. Haven't dropped the pan yet though because I live in Utah and it's been the worst winter we've had in the last 50 years so I haven't been able to do much. That was important though so I did it in the snow lol. I changed the thermostat and water pump. I'm gonna do diff fluid and a pan drop on the transmission to check the magnet soon. I am considering flipping the pill in the transmission lines too so that the transmission runs cooler. Other than that everything else seems fine. It already has new brakes and tires. I need to do some paint correction on the hood because it's a little faded. Planning on putting a lift, intake, new bigger tires, and putting a tuner on it. 20230329_120141.jpgResized_Resized_20221202_142655(2).jpeg
 

Sam Harris

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Good stuff! Looking forward to the progression of your rig. Thanks for including some pics. You have a tune in mind? Going to buy HPTuners and learn to do it yourself?
 

Mean_Green

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May just be the picture and the concrete background, but I don't see any center tip electrodes left on the two left plugs. The other three have some showing. Enlarging the picture a lot, I see a little on the first plug, but not on the second. But again, it might just be the concrete that's hiding them.
 

GMCnewbee

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Sure, those spark plugs look normal for that many miles. Modern ignition systems are great. I remember the days of spark plugs not lasting past 50k miles and most times less than that. Today I would not go past 100k, and even that is a gift. Yes the engine was running, but those plugs are way past their time for retirement.
 

Fless

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Sure, those spark plugs look normal for that many miles. Modern ignition systems are great. I remember the days of spark plugs not lasting past 50k miles and most times less than that. Today I would not go past 100k, and even that is a gift. Yes the engine was running, but those plugs are way past their time for retirement.

Agree, just heavily worn; center electrodes are there. You're probably correct that they're original. Someone got his money's worth out of them.
 
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Cryptothedog

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Yeah they definitely needed it. It didn't run bad before but I do notice quite an increase in power that I didn't know it originally had lol
 

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