Spark plugs?

[Jimmy Brooks]

I was going through my maintenance of what I needed to have done within the next month and I realized that I had never replaced my spark plugs at 105k. I current have 131k on the truck and it still runs great, no lack of power, no rough idle, no check engine light, the car runs absolutely perfect. so I’ve come to the question of do I even replace them Or at least do I have to worry about it now or later. I know a decent amount about engines but would I be risking anything other then damaging the cats if a plug dies and it misfires? Let me know of anymore things that I should worry about, or if it’s not worth worrying about now. Thanks!

 

[ryanjl]

I changed my plugs at around 100k miles and the plugs I took out made it look like a job that did not need to be done then. 131k might be pushing it, though.

It's not an overly difficult job, but just be prepared to take things apart to get to them. For example, on the passenger side, it was so much easier for me to remove the battery box and other stuff than try to work around it.

Have some extensions, and a small little torx ratchet like this will help:

https://www.amazon.com/gp/product/B077YFVC3W/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

You need the torx to remove the coils, and some of the torx bolts are harder to get to.

 

[f1racer328]

I'm having the same dilemma. 105k miles, never touched the plugs and I don't see a reason to.

My uncle (mechanic) says there's probably no reason to change them unless they start acting up.

 

[Jimmy Brooks]

I'm having the same dilemma. 105k miles, never touched the plugs and I don't see a reason to.

My uncle (mechanic) says there's probably no reason to change them unless they start acting up.

Exactly my situation but with my dad. my fear is just leaving them in too long and it possibly warping to the block or corroding it. but then again, I’m not sure if what I said is exactly true, it’s just what I’ve heard. also with gas prices rising I’m worried I could be getting worse Gas mileage on the old plugs and possibly wearing out the coils.

 

[ryanjl]

Here's my post (with photos of the old plugs) from when I did mine at around 100k miles:

LR4 v8 5.0l Spark Plug DIY

Great video! Everyone has their own techniques and I do agree that it's easier to get to them if you pull out the battery sidings. What I don't agree is that this is an easy job. It takes more than an hour, even if you're super efficient. With that said, throw some Denso Long Life Iridiums in...

www.landroverworld.org

 

[ktm525]

It's a straightforward job and I disagree about leaving them too long. A couple of mine had rusty threads and backed out with some resistance. I would worry about them eventually corroding themselves stuck. At a 130k miles you are at least 1/2 through the expected lifetime of the engine. Keep in mind the NGK plugs changed a heat range from what they left the factory flor with (V8s)

Here are the old ones at about 100k miles. 6C10 came out. 7C10s went in

 

[Jimmy Brooks]

It's a straightforward job and I disagree about leaving them too long. A couple of mine had rusty threads and backed out with some resistance. I would worry about them eventually corroding themselves stuck. At a 130k miles you are at least 1/2 through the expected lifetime of the engine. Keep in mind the NGK plugs changed a heat range from what they left the factory flor with (V8s)

Here are the old ones at about 100k miles. 6C10 came out. 7C10s went in

View attachment 21841View attachment 21842

When you talk about heat range are you sayings the 6c’s are worse then the 7c’s are? I do have a 2010 so id think some of them are probably starting, if not, slightly corroded already.

 

[djkaosone]

Spark plugs, you can touch them, it's consensual. You should change them out at least once every 5 years. I've seen them go longer for sure, but I've noticed electrodes burning out earlier than 3 years too. I highly recommend Denso Iridium Long Life, it's a personal preference. I like Denso over NGK, it's debatable.

I had this conversation with my brother-in-law and he hasn't changed his 2000 Lexus LX470 plugs since he bought it new. He continued another 1000 miles and low-n-behold it detonated and blew out the top threads of the head and spark plug. The spark plug ceramic had a crack and the electrode sparked/blew out to the top threads causing him to lose compression. He can't get a compression test over 95 psi on that cylinder. It's good enough to drive around town, but anything under heavy load gives him misfires in that cylinder. Just saying... don't be afraid to touch the spark plugs.

 

[ktm525]

When you talk about heat range are you sayings the 6c’s are worse then the 7c’s are? I do have a 2010 so id think some of them are probably starting, if not, slightly corroded already.

6C10 are not available. They were replaced by the 7C10s

 

[Quijote]

I'm having the same dilemma. 105k miles, never touched the plugs and I don't see a reason to.

My uncle (mechanic) says there's probably no reason to change them unless they start acting up.

My 2018 BMW M3 requires spark plugs changed every three years no matter what. Mine were changed at ~10k miles. Luckily it was covered under the free maintenance program.