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Spark plugs and anti-seize compound

Ideas about the type of compound I should use?

I’m changing plugs on my '90 Dodge Ram 50 (a mini truck) and I would like your thoughts on what type of anti-seize compound I should use on them prior install. I already have one plug that is “hesitating” to be removed and, since I’m putting new ones in, I really want to prevent this from happening in future.(I live wayyyy out in the middle of the Mojave Desert and so a real mechanic is not available if I screw this up.)

Added info if any or you have a more technical bent: I am using Autolite plugs and the head they are going.
into is aluminum.

ps. to help get the recalcitrant plug out, I’m going to spray it with Kano Kriol. Better, imnsho, than WD40. :slight_smile:

A lot of spark plug manufacturers recommend AGAINST the use of anti-seize

I would carefully chase the threads in the cylinder head


If these are regular plugs, and not platinum or other exotic metal, then this works great.


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Gosh you people are fast!

I just revisited the Autolite site and consulted both manuals on this truck. None of them provide any advice on the subject. I have learned, however, that there seems in some cases to be an issue with peeps globing compound on the plug, and that,apparently, can change a plugs ability to dissipate heat. And such like.

THANK you for responding, db4690 !

I think that’s what I thought about getting. Just needed to see it, “Tester.” Thanks much for your help!

I would replace the spark plugs with either Champion, Denso, or NGK spark plugs.

I would not, nor do I ever, use anti-seize on spark plugs, with the exception of one late-model Ford engine. And for that application I use a nickel-based anti-seize.


The anti-seize recommended by tester is the correct anti-seize for an aluminum/iron mating surface. The general rule is if the plug has an anti-seize plating, which has a silvery finish, do not use the paste. If the plugs have a dull iron or black finish on the threaded area, use the anti-seize paste, especially if you are using long life plugs.

As for the glopping, the issue is when you use too much paste that it gets into the combustion chamber area where is could potentially short out the electrodes. Confine the paste to the threads of the plug only, do not try to put the paste on the threads in the head as this will get forced into the combustion chamber. Do not allow the paste to go beyond the threads of the plug at either end.

You should also use some dielectric grease inside the spark plug boot to prevent any arcing externally on the plug. Do not worry if some gets on the contacts, it will not affect the spark.

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My opinion: Chase the threads to clean them up, and use a very small amount of the anti-seize @Tester posted. I’ve been doing this for maybe 30 years without a problem.

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Is there a specific reason you want to use anti-seize compound on your spark plugs? Were the old ones hard to get out for some reason? Does the owner’s manual or the repair manual call for using anti-seize compound on them? If not, I wouldn’t use it, because I’d be afraid of one coming loose and popping out, which can be pretty scary and can cause significant damage.

As long as you torque the plugs to the manufacturer’s specified value, using a torque wrench, I don’t think you’ll need anti-seize compound.

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If you use NGK plugs - NGK plug threads are sink coated and they have a warning NOT to use any anti-seize compound


Read OP’s first post…

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I did, and I’m not sure what “‘hesitating’ to be removed” means. Had it seized? Was it completely fused? Was it cross-threaded? Was it over-torqued?

Knowing more about the problem might help since spark plugs are not sentient beings.

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I applied enough torque with the ratchet that I got to the point where I thought it best that I stop, apply some Kroil oil, give that a chance to do its job., then try again.

Sorry for the delayed response, but I have a job on the internet, and if I don’t concentrate on that, I can lose significant $$$.

Good suggestion, and a thread chaser will be delivered to me today. So THANKS to you, sir.

Thanks, asemaster!! I’m re-thinking the use of any compound at all. And Sorry for the delayed response, but I have a job on the internet, and if I don’t concentrate on that, I can lose significant $$$.

When I hold a spark plug up in front of me, the gasket on the plug is definitely silver-ish, but the threaded part of the plug is not as ‘bright’ as the gasket and does not have what I would consider a ‘silvery finish.’

If I decided to use the anti-seize compound, I will use it sparsely. :slight_smile:

Thank you for your input, Keith. I really do appreciate the time and effort you put into this.

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Next go around I’ll use NGKs, but my finances are such that I’ve got to use the plugs I just bought. Thanks, asemaster, for your help!

I’m having a bit of trouble – perhaps because I’m being too cautious – getting one plug out. I do not want this to happen again. I live wayyyy out in the middle of the Mojave Desert. In future, if I have trouble getting a plug out and it breaks such that part of the plug is stuck in the block, I have no real mechanic available to set things right.

I’ve Chilton and Haynes manuals; neither address the subject. ( Things are different when you live ‘outside of civilization.’ For instance, this town has 125 people in it - none of us use a street address because our one-person post office doesn’t deliver to street address, only PO Boxes; at times, that makes it a bit difficult ordering stuff on the internet. Taking “whatever” to a mechanic entrails a 110-mile drive. Go to google images and type in “desert center, california” to get a glimpse of where I live. :slight_smile: )

And thanks for you info on use of a torque wrench. I do appreciate you help, Whitey!

When removing spark plugs from aluminum heads is difficult it’s a crap shoot to decide what the best option is for replacing them. I used a thread chaser with the anti-seize noted above on the first few threads and installed the factory correct plugs leaving the anti-seize in the holes. Spark plugs blowing out of holes where the previous plug was seized is somewhat common and on a few occasions I sent the car on its way without doing any work due to the likelihood of being blamed for the damage caused by prior lack of maintenance.

Permatex anti-seize is available in a stick and I prefered it.

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I would be careful about using too much penetrating oil, but it might be your only hope. I once read a warning that if it leaks past the plug, it can do internal damage to the engine. I think I read that here somewhere.

If it was my vehicle, I’d try to gently loosen the plug with a 16" breaker bar so I’d have the leverage to do it gently. I might make a gentle attempt to loosen it, walk away from it for a while, and then take another gentle effort to loosen it again later, repeating the process several times. Think of the plug like the lid on a jar of pickles. After someone has tried to get it open, he hands it to you and it opens with very little effort, and you say, “You must have loosened it.”

Another idea might be to try gently loosening the plug on a warm engine instead of a cold engine. Maybe the metal surrounding the plug might expand slightly more than the plug itself.

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