Changing spark plugs

Assuming the O2 sensors weren't screwed into aluminum, so not a correct comparison.
I've been changing spark plugs for over 30 years and on vehicles with aluminum heads and I've never had issues taking plugs out that didn't have anti-seize on them except in this one case. She got the engine hot one time some years back and that is probably why I had an issue.

If people want to use anti-seize, have at it. I don't use it and don't plan on it.
To the OP - If you have never done it before might be worth finding a shop buddy who has, so they can sort of guide you along the first time. I think the biggest issue is cross threading when putting them back in, or over-tightening - so be patient. If the plug was going to break coming out, it would likely break for a certified mechanic also so pay now or later.

For Never Seize - NGK applies a chemical coating to the threads in the factory. The coating is a oxidization inhibitor and also acts as a release agent to get the plugs out. Putting never seize on them can disrupt this protectant and make things worse. I have done many NKG plugs at 100K, including taking them out again myself at 200K, and never had an issue.

I don't know about other brands, and its your car do what you want. also acts as,and/or metal shell stretch.
Tearing the boot when removing the old coil Accidentally cross threading the plug on installation.
Using incorrect torque.
Breaking the ceramic.
Stripping the threads when removing a stubborn plug.
I’ve done a handful of cars without issues. Only ones I pay a shop to do are Subaru plugs since they’re on the side of the motor, along the frame rail.

I just did my F150 the other day and PO didn’t use anti seize on the plugs. I mean they were done at most 3 years/20k miles ago so they weren’t seized up, although without anti seize I genuinely thought they were. When I got better leverage they came out with ease.

Unless you own a car that’s known for broken plugs(ford 5.4) I wouldn’t sweat it. Just make sure you use a 6 point socket, the correct size, and make sure the wrench extension is actually straight before cranking on it
Maybe if the last person to install plugs did, you wouldn't have had this problem
You did read what I posted. The most difficult plugs in aluminum heads that I have removed HAD ANTISEIZE ON THE THREADS.
Normal antiseize is for areas where rusting is an issue, and will harden and dry out with the high heat at a spark plug. It turns to a hard cake like material that will promote seizing.
Yes I read it. What kind of antiseize was used? The cheap zinc or copper based variety?
Cheap? Nothing is cheap now. And no the antisneeze was not from china. Actually it has been many different types even special stuff meant for aviation spark plugs, as well as some that came with the plugs. I do have some special stuff I may try at some point in time though, but not on anything I care about, just a test engine.
IMHO, the anxiety about removing plugs from aluminum heads comes from using a 3/8 ratchet wrench with the sparkplug socket which in most cases is a 3/8” drive.

If those spark plugs were in the head for 100,000 miles which means usually 8 to 10 years they are typically TIGHT. Do yourself a favour and cross over to a 1/2 inch ratchet for more leverage. Also, when the plug busts loose there may be a mighty squeal. Don’t let it psyche you out. This is what drives people towards anti-seize, good or bad.

The good news is, if you use Iridiums and change the out to another set of Iridiums, chances are you’ll never have to do that vehicle again as very few people keep their vehicle for 200,000 miles.
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My advice to anyone changing plugs, especially with coil on plug, is to be careful with those small M6 bolts, usually on the coil packs.

Don't overtighten them, they don't need much torque, if you break one then you really created a monster headache and likely a non-drivable condition.

The average LESS than 90 INCH-POUNDS of torque isn't much, check the specs if you aren't seasoned.

Having a set of 3/8 drive extensions, especially the very short ones help on some engines, as well as a pivoting ratchet for hard to reach plugs.
Modern spark plugs with Iridium electrodes can last almost indefinitely. However, they can fail if the gas seals start to leak. In many cases, the recommended plug change interval is set so that the plugs will be replaced before any gas leakage begins.

The thing to avoid is damaging the threads in the cylinder head. Sometimes, depending on the engine, getting the new plug started in the thread is out of the mechanic's sight line, done by "feel". If its not starting in the thread easily, be careful, try again.

Its not like the old days when a set of plugs in a high performance engine was good for maybe 6000 miles. Fuel injection and modern ignitions are a great advance over carburetors, leaded fuel, and points and condenser, distributor cap ignitions with iron core plugs.
Regarding installing new plugs, I use a rubber spark-plug boot over the new plug. I turn the plug back (CCW) until it clicks, and then forward (CW). The threads usually engage properly. If they haven't, the rubber boot will quickly start to twist, or will slip on the plug's porcelain insulator. This method does not allow enough torque to be applied to damage the threads.

And yes, I remember the old leaded-gas/points ignition days, when the debate was whether to change the plugs twice a year or every 10,000 miles.