As I see it, anti-seize provides at least the following benefits: (1) when correctly selected for the application, it supplies additional sacrificial-anode material; (2) it seals the threads to some extent, which prevents/slows entry of "electrolyte" into the threaded connection (no electrolyte means no electrochemical reaction can take place); (3) it minimizes galling of the threads; and (4) for a given torque spec, it promotes a more consistent/repeatable preload (stretch) of the fastener. Of course, it is common knowledge that torque specifications for "lubricated" and "clean and dry" threads are different. If choosing to use anti-seize on spark plugs, my recommendation is to USE IT SPARINGLY. Contaminating either the porcelain nose or the external insulator can lead to problems, such as misfire and possibly even damage to ignition components, so it is CRITICAL TO KEEP ONE'S HANDS CLEAN when installing the plugs. Also, when applying anti-seize to the threads, I would keep it off the first couple AND the last few threads (the latter precaution to prevent any lube from being transferred to the washer/seat of the plug and potentially affecting heat transfer/electrical contact in that area). By the way -- thank you, everyone, for pitching in! There are many great comments, detailing viewers' first-hand experiences. To me, this is really about people exchanging and discussing different viewpoints on this seemingly simple issue. I hope all of us can learn something. I know I have.

I'm 66, ase mechanic, worked on Subarus since 1973. My brother ( mechanical engineer) got to the bottom of seizing champion brand plugs. He said NGK had gold anodized antisieze and ROLLED THREADS, champion brand was CUT THREADS and no anodized antisieze . Subaru manual said NGK once removed was to be discarded, not reused. By 1975 I antisieze all plugs going into aluminum! NEVER HAD ONE COMEBACK, NEVER.

I've been using antiseize for over 30 years on plugs. From old air cooled vw's to newer vehicles and have not once had any issue. I'll keep using it. Don't care what the manufacturer states.

I started working on cars at 12 in my uncle's auto repair biz. That was in '65. One of the 1st jobs I became proficient at was gaping & installing plugs; typically my uncle would take the hard, (AC) on installs. He usually removed them out, due to me having 12 yo arms. He'd put the plugs down on my end of the bench, I'd spec the car engine, gap 'em & we'd install 'em. He worked on zero imports. By my mid 20's, I was a Toyota specialist, but worked on all imports. By 30, I had my uncle doing domestic AND foreign repair. In my teens, I was building drag cars & racing; an older drag racing mentor was building a new A/Gas 65 Chevy II. His previous, a shoebox '64 was a 2 time national ET record holder for their class. His new 14:1 302 SBC would not run at 3000+ RPM's. The local Chev dealership helped me w/ parts expense on my C/Gas '57 wagon. An out of town dealership was a major sponsor of his '65, so he ran AC Delco, like I did. There were no NGK's at parts stores, none, zero, zip. We rarely saw aluminum heads unless it was a fuel hemi or big $ BBC, (NOT in my teens, at all). We tested AC plugs for 3 hrs. 50% failed to fire at +150psi. I went to the local Honda dealer where a friend was an apprentice. I knew the 2 brothers-owners cause I made their weekend breakfasts at my sister's cafe, early in high school. The apprentice & I had a mutual friend working on cars in AK. He'd said the only plug working reliably in -40⁰F, Fairbanks was NGK & I should try them in my SBC's. We crossed AC to Champion to Autolite to get an NGK number close enough. 8 NGK's solved the problem. Plugs have 2 coatings, zinc dichromate or black oxide, (IE Autolite). Black is NOT raw steel. I learned about NevaSeize on plugs that Sat @ the Honda shop. My friend gave me some & said it made R&Ring plugs much easier, plus they'd damage a ton of M/C heads without it. My mentor was military trained in electronics & liked the NevaSeize for a possibly improved electrical connection. (It is, afterall, powdered aluminum (silver ver) or powdered copper, (brown ver) in a oil suspension; make a superior heat sink compound I learned, (in my 50's!) We both liked the idea of easy to R&R plugs, plugs less thread damage/chance of cross threading. By the late 80's plugs in alum was common place. I've done repeat work on multiple dozen's of cars & trucks in my life. NEVER did I experience plug or alum head damage. Neither have the mainly mechanics I've trained or know. How do I know? In my machanic life I met exactly 2 pro mechanics who used NevaSeize. I taught the rest. If head or plug failure happen, some would have tracked me down to exact revenge. Look at the example pic of potential plug damage; 1 image looks like complete rupture of the thread barrel. I've met guys who've ½ air impacted plugs in, on a dare, & THEY never ruptured a thread bsrrel. If someone is blaiming NevaSeize on the thread barrel damage, they're talking out their arse. As far as over tighening, a competent, pro mechanic will not, because they now what a PITA & expense), plug thread can be. No sane person would inflict that on themselves. Therein lies the key point of NGK's communication. It is written by competent mechanics, then edited by corp attorneys & loss mitigation specialists. NGK cannot control who buys & installs their plugs, so they have to protect themselves from the idiots of the world who have no connection between their brains & arm muscles. Continue using NevaSeize, you will not be doing yourself or customers wrong. What you should add to every diag list for any rough running, unknown car is a compression test. I never had a tune up, (in the old ages wheh they were a thing), come back for anything other than a failed component. I weeded out the bad valves/rings BEFORE the tune up was done. Guys used to say they could do it w/ a scope; never proved it, though. I'd think a quick, engine hot compression test would still do for you what it did for me, removed the speculation & either guessing or much more diagnostics about hard part problems before spending customer $ on components. In my day, it was ignition, now it's sensors or control units. It's a well invested 10 minutes in YOUR rep as a pro mechanic. GeoD

A great video and discussion on the topic, especially covering the additional torque that is generated when using a lubricant on the threads. However, ever since seeing a friends car have a coroded spark plug snap in two on removal (aluminium head) and requiring far too much effort from the mechanic to extract, I've always put never-sieze on my sparkplugs to minimise the corosion, create a better seal, and ensure they can be removed easier at a later date. 30+ years and this method is still working great for me and my family.

Excellent video!! I don't care what anyone says, all of my spark plugs will get anti seize with a 30% torque reduction!! I see time and time again these idiots in the comment section regurgitating not to use it, and I can only wonder if they are running a machine shop fixing stripped aluminum heads, haha!! And just like you demonstrate what happens to the factory coating after numerous heating and cooling cycles perfectly illustrates why to use anti seize!

Honda's service manuals recommend anti-seize and provides a torque spec that assumes anti-seize is used. NGK, on the the other hand, specifies an angle not a torque. If either are respected then it won't be too tight. NGK's angle spec is impossible to overtighten regardless of use of antiseize. If someone used a dry torque spec and then added anti-seize then that would run into a problem (as NGK's bulletin described).

Very clear and thoroughly explained. Thank you for discussing the scientific reasoning behind your suggestions, I haven’t seen many videos that do so.

Great analysis! I AGREE! I am 71yrs old & have used antiseize for decades. Living in the rust belt, we MUST use it. NEVER had overtorqueing problems & agree, just drop torque specs if problems. Just apply a THIN coat. Two dissimilar metals? Dog gone right, antiseize it.

Most gasketed spark plugs tightening recommendations are either torque or finger tight with the gasket against the head then 1/2 to 5/8 turn. Taper seat is torque only. I use the 1/2 to 5/8 turn method and don't have any problem. I also think the antiseize promotes better heat transfer to the head. I use only aluminum antiseize because I work in the salt water environment and galvanic corrosion is very high. The aluminum antiseize is extremely good for stainless on stainless fasteners to prevent them from galling when assembled. Grease doesn't do the job. Just a very little bit of this stuff seems to get everywhere so I would caution getting any at all on the firing tip because it might short and foul the spark or any other electrical connection. I use the squeeze tube because it is easier to control the messiness and so little is needed for it to work.

I have been using antiseize on spark plugs for a very long time. I also use a torque wrench. I have never had an issue with the threads in aluminum or cast iron heads. I have never broken a spark plug as depicted in the NGK picture but I have broken a small few by having the socket go on an angle when tightening so I have learned to keep the socket, extension and ratchet in a perpendicular position. My only precaution is to not lather up the threads and to keep it away from the electrodes, you do not want antiseize getting into a cylinder. IMHO, use it on all spark plugs and stop fretting over it. Those depicted NGK spark plugs must be made with recycled Chinese steel.

ALL of these comments are spectacular! A ton of info to answer any question one might have on the subject. The reward of an excellent presentation, hats off to you Sir!

Working in the Marine Industry for many years we always used Anti Seize compounds on Stainless Steel propeller shaft splines for Brass & Aluminum Props. Weather they were going in fresh or salt water it was a requirement.

Excellent analysis. Some people are allergic to Nickel, just a heads up. Other metals that can cause skin allergies are Cobalt, Chromium, and Zinc.

Keep in mind most torque specs are intended for use on clean and lubrrcated items. Inconsistencies in thread condition such as corrosion, debris, lube presence or even type of lube can greatly affect clamping force provided at a given torque. At higher torque the variation in clamping force can get kind of crazy. This is why on critical items such as rod bolts, the preferred method is torque + an angle. Torge to a lesser value before the variation gets out of hand and then to an angle to achieve desired final torque. The rod bolts are measured of stretch to insure correct clamping force. Even this is not fool proof and there will be variation in acquired clamping force but it is the most consistent method I know of. Back to spark plugs. In the scheme of things torque related, they are not critical and do not require much torque to do what is required. The gasket type plugs must be tight enough to compress the gasket to form a good seal and not back out. The taper style must seal on the tapered area and not back out. This is mostly all that is required. Using anti sieze will help prevent damage to the threads in the engine head and will aid in sparkplug removal. As I see it there is no downside to using it except it is messy. It will prevent a 20 minute spark plug change becoming a two day head replacement. This is actually a common thing. Ask a Ford guy.

I always use antiseize on spark plugs! Removing a cylinder head for repair is no fun and gets expensive!

I use zinc anti seize in every spark plug installation. Most plugs will bottom out when the crush washer is crushed. Torquing then stops.You will feel this point of resistance and stop. Unless you have gorilla hands there will be no problem. Lubricant and torquing really plays no role once the washer is crushed to seal .Makes it a lot easier to remove later on.

I always get that feeling I should cut back the torque when using any kinda lube, thanks for confirming this! :D

Awesome! You have clearly broken out of being a 'Technician' and are now clearly a genuine 'Mechanic'.

I always use a very light coating of anti-seize, except when installing a plug in a cast iron head. And I don't tighten a plug to a torque value. I tighten the plug until the gasket just touches the head, then continue to tighten the plug until the resistance to tightening it rises abruptly (typically a 1/2 turn). I use the same procedure for tapered plugs (no gasket), but they only need 1/16 - 1/8 of a turn past finger tight. And I've never stripped a cylinder head or a plug.

Back in the late 70's, i had a spark plug seize in the head of my engine. It had been installed originally by myself, properly, dry and set on the washers. When it came time to replace, it was locked in place, and I managed to twist off the plug from the threads. The 4 banger ran, but sounded like an old time steam engine - chuf!- chuf!, chuf!. A local garage BROKE their easy-out trying to remove it. Last recourse was an engine rebuild shop that fixed the head. Used anti-seize after that. In those days, the plugs may not have had that plating on the threads, just bare steel.

I even use the factory specified Castrol anti-seize (looks like Permatex 133H - silver) on the factory aluminum lug nuts on my Porsche 911 (993 series). They get torqued to 130 Nm or 96 lbf.ft. as called for in the factory manual.

I've been in the automotive scene for more than 2 decades and still see antiseize on plugs and wheel bolts. It might be common knowledge, but a lot of folks don't have common sense and need to be educated or re-educated.

I just removed some original BMW ( Beru) from a bmw e46. They hadn’t ever been out in 21 years. The car was well below the 90k miles for change so they were never changed during services. They came straight out. So the plating certainly worked

Been changing plugs in aluminum heads using anti seize since 1977ish. It's pretty easy to "feel" the crush washer deform to the head and then begin to tighten. That's all you need. No torque wrench needed. Just did my Tacoma a few days ago. Easy peezy lemon squeezy.

Thanks for this. That's answered a lingering spark plug knowledge gap very well. Also, Coming from long term marine experience, *copper-based anti-seize is really bad for alu connections.* Long version: When you 1st put it on, it seems ok. And if you take apart, clean, and reapply to that connection frequently, it's fine. (eg don't ignore it for 1 year at marine use). But we learned the hard way again and again: if you have a connection that you aren't servicing a lot, and it goes for 1 year, *the corrosion protection additives will get used up, and your mixed-metal anti-seize will turn into a corrosion promoter.* Certain anti-seize compounds are ok (zinc) as is *dielectric grease, as long as it isn't too hot* (don't use on turbo mounting studs). Dielectric was already designed to help prevent corrosion and isn't adding any mixed metals, so it works surprisingly well as a general purpose compound. 1 further note: I _wouldn't_ substitute Dielectric grease for anti-galling compound for SS on SS connections.

Fantastic information, especially if plugs are removed for inspection then reinstalled. I never use a torque wrench to reinstall plugs. They have a crush washer and and bring them up snug tight and don't moose them in.

When I apply anti-seize, I put a flash coating on the threads using a clean dry brush instead of one with a gob of anti-seize on it. The coating is so thin, it looks more like a spray-on coating.

I love your command of the English language. You’re a smart guy.

I have been installing spark plugs for some 50 years and I have always applied anti-seize and never used a torque wrench. I screw the plugs in by hand until they are bottomed and then tightened them by one flat or 60 degrees and have never, ever had one strip or come loose. Do be aware that you should always ensure that you do not apply the anti seize compound any closer that the last three (3) threads on the spark plug as it can melt and flow down the plug with the potential to short it to ground.

Spark plug Einstein nice well documented video! So when will you come to my house and help a brother out 😂😂

I love the great in depth, thanks

I've always used anti-seize, not knowing why it worked. I figured it kept fouling from working up the threads, which would result in a seized plug, then subsequent breakage or thread stripping. It also has been useful for hand-tightening since it lubricates. A reasonable torque on the spark plug or 1/8" turn past hand tight has worked well in 100's of plugs. I've never had one come loose or break off.

My engine manual says 18Nm torque for the spark plugs. I can not imagine that they will overstretch even when lubricated with that low torque. I am in doubt if is possible to overstretch a spark plug made out of steel in aluminium treads.

I put a extremely small amount on my sp threads and ran it through to coat the entire thread, then remove and let dry, then i would have a nice thin coating of anti-sieze to help stop corrosion and/or stubborn to remove plugs. Not on every engine I have, but on some :-D

I really appreciate your analysis on aluminum cylinder heads and I highly recommend I always use anti-seize on spark plugs and very careful tighten them up like you said I agree with everything that you say you sound like a and talk like a very educated professors with metals and lubricants

I use Autolite Platinum Spark Plug AP5125 and anti-seize on my 1992 F150 4.9 I6 never had a problem!

Champion Aerospace 2612 Spark Plug Thread Lubricant is an old aviation standby. If you think car parts are expensive try aircraft! It's easy not to overtighten. I've NEVER done that in over forty years working on delicate motorcycle spark plugs let alone car plugs. Many "mechanics" who never worked on anything delicate or precise treat spark plugs like lug nuts. I've had to fix stuff they buggered but every stuck spark plug I dealt with was either corroded due to moisture intrusion or crossthreaded. None were stretched to failure. I use Time-Serts for thread repair after grinding a SMALL notch in the rim. Install Time-Sert, drill hole centered on notch slightly smaller than a section of steel finishing nail, fill with JB Weld (takes very little) then drift a short (about 1/4") pin you cut from a finish nail. That pin cannot escape because the plug traps it. Old aircooled motorcycles require frequent plug swaps, much more often than cars and these have never had a customer comeback at the shop where my Vincent-restoring mentor taught me the trick. He'd been wrenching motorcycles since the 1950s. Both of us were USAF crew chiefs and I was also a jet engine mech.

I will make this real clear for people abusing this subject, anti seize compound for spark plug was mainly designed for air cooled engines. All other engines use some oil.

I had to replace the aluminium cyl head on my motor because 3 of the 6 NGK plugs without lubricant had seized in it, to such an extent I broke one of them trying to remove it, the ali picked up in the thread. I have always lubed spark plugs on installation and so far the only plug I have ever broken is the one in this head trying to remove it.

I used Dupont Molykote P-74 anti seize, which is made for SP's. P-74 contains no metals. A very super light coating. No issues with NGK plugs.

Many times, spark plugs going in without anti-seize feel like cross threading is happening. That's why I used anti-seize. Iridium plugs that have been in an engine for 120,000 miles on them, are often hard to get out with stripping head possible. Mechanics do a slow back and forth loosening of plugs in this case.

GM issued a TSB warning of the use of anti- seize on spark plugs. It inhibits the transfer of heat to the cylinder head, causing the plug to be hotter and shortening its life. Best practice is to remove plugs and run a thread chaser and lube threads with engine oil at regular intervals. Anti- seize is for those who leave the plugs in for extended periods without removal.

those plugs with crush washers: tighten until the washer is crushed, then stop. That doesn't change wether you use anti-seize or not. A torque wrench is not needed, but a bit of feel is.

I use anti-seize on my NGK plugs. I don't use a torque wrench. On the box of the NGK plugs I buy, it gives instructions to turn 3/4 of a turn after the crush washer makes contact. If I wasn't using anti-seize, I'd still follow the box instructions. I don't trust the clean torque value on old threads. You can feel when tightening replacement plugs, they don't all have the same feel. Some go in a little tighter from carbon fouling in the threads of the cylinder head, so you'll be under-torquing those using a torque wrench. If there's no instructions on the box, only then will I use a torque wrench and torque to spec (-20% if using anti-seize).

GR8T stuff :O) I'm now a fan. Cheers from So.CA.USA 3rd House On the Left

I always use anti sieze, and my internal torque wrench, never had an issue.

Honda automobile service manuals call for antiseize. I'm referring to the factory printed soft cover paper service manuals covering autos, 1970s, 1980s, 1990s, at a specific torque specification. All models had aluminum heads. That is how I roll.

What does that table say about this scenario? I put some cheap blue anodized valve caps on my wheels. 6 months later I went to check my tire pressure and they were all seized up and had a white ring at the base of the cap. I had to resort to vertical cuts with a dremel, and pry them off. All the threads on the valve stem were packed with a dry caked up powder

Whoever broke those spark plugs must have tightened them like Hercules. I'm surprised they did not strip the threads. They dont need to be that tight with anti seize or not.

Awesome video. Never thought about the galvanic corrosion issue. I ran across someone who said not use the aluminun antiseize on sparkplugs because it hardens up and becomes stuck do to heat. For this reason i use a high temp nickle antiseize. But now i wonder if nickle is a wise choice due to galvanic corrosion.

If using anti-seize follow instructions on package of having plug bottom out and then no more than 1/4 turn addition. This will feel loose but only because anti-seize is so slippery. Also, use small wrench which isn't so easy to over torque with.

Thank you for your knowledge and video's USA 🇺🇸

If you have been a mechanic any length of time you probably whont use a torque wrench when installing spark plugs

Every time that I used anti seize on my toyota tacoma 2tr-fe engine, the plugs were hard to remove. Have not used it since. Now thay come out like thay should. A friend used anti seize and took two hours to remove one spark plug.

Here at NKG we are using less conventional metals that are softer and easier on our tooling with a bonus that the source material is very cheap. To combat complaints of our plugs literally twisting off at the base, because we made the threaded shells too thin, we have put together this information packet that masks build quality problems with carefully selected wording and use cases while simultaneously shifting the blame to the installer.

very good information. thank you..

Thanks for putting this up.👍What you say about decreasing the torque by 30% or so makes a lot of sense. I changed the spark plugs in my daughter's car and one of them was corroded, and misfiring. Is there a way to clean the mild corrosion on the engine block around that spark plug?

Thankyou. Great content.

I always use a whisper of nickel anti-sieze on plug threads - it handles the heat. Regular is often junk and just doesn't hold up over time. How the heck people have snapped threads off is beyond me. In decades of wrenching, if I break something its a steel bolt in aluminum that was probably installed dry and lived in a salt environment for years. Saying a plug does not "require" anything brings some assumptions with it, like a minimum miles per year driving to get at a reasonable replacement schedule. For low miles drivers [like me], their advice might disappoint because time in service is what will matter for these coatings. Well covered. What I was able to dig up on the Versachem B product was lithium grease/petroleum distillates with... copper, calcium oxide, graphite, with remainder [roughly 5%] as proprietary.

if you ever have to repair damage spark plug thread. you ask yourself why didn't it have anti sieze

I always dab a little on the threads. I build drag cars and we are constantly replacing spark plugs, in/out-in/out and so on. We use a hotter plug just to warm the motor/oil up then switch to a cold plug and pull it to the line, start it and make the run then shut down at the end and get towed back. When back the plugs get pulled to be read. Anti-seize goes a long way with preserving the thread integrity in the heads. Just do not over-tighten although I've cranked on quite a few 14mm thread plugs while indexing and NEVER broke one in 25+ years even with anti-seize. I've pulled threads in soft heads before.

Looks like when you apply antisieze, the concern will be the torque being applied during installation. Do you have an idea of how much torque (range) will break a spark plug?

I'm calling BS on NGK. I tighten by crusing the crush washer, not by torque reading. I also lube all wheel studs due to the salt environment. I've broken off many seized lugs, but never pulled one in a lifetime (50+ years of wrenching) 1/2 turn after firm contact will not pull a spark plug in half. Maybe chinesium. I have been using anti-seize since reading a 2007 Toyota TSP asking dealers to remove the plugs from new engines and apply anti-seize. I owned the engine in question and the plugs to date are nearly identical. I also never use NGK plugs. I prefer to use Delco in GM and Denso in Toyotas, Motocraft in Ford. I notice that now the Denso plugs feature silver paint on the threads which is old-school anti-seize. I just installed a Denso oxygen sensor and applied Denso anti-seize that came with it. Same crush washer system.

Super Presentation!!! I have a great running 302,000 mile ‘07 Toy Yaris I’ve owned since nearly new. I waited until 217,000 miles to change the original plugs… It took quite a bit of force to free them…I was quite afraid they were going to strip! Q. I’m curious as to how much of that friction was the threads vs seat friction? And yea…I applied anti-seize and eased off on the torque on the new ones. Bout time to change again.

Last question… I’m seeming to experiencing a bit of difficulty sourcing zinc anti. Really don’t trust eBay sellers…AT ALL! What zinc formulation/composition do you suggest? Around 4oz is plenty for me.

Had to turn the volume way up to watch this video!

My moms 1.6l ford escape has the galvanic corrosion on two of the four spark plugs. I was lucky to be able to remove 3 of them, the 4th one broke, now i have to deal with extraction. Definately not thrilled. I was even less thrilled when i double checked the owners manual, for reccomended spark pluv interval of 100k. My vehicle only has 70k. I am topping up antifreeze, but very minimal. System consumes about 12oz bottle of water every 45-60 days. I borescope every cylinder, and i am not sure what i am seeing. Definately reccomend removing all plugs, and put a pressure tester on the system overnight, hopefully (actually not hopefully 😂) i may find coolant intrusion in the combustion chambers of my two problem holes...

LOCTITE LB 8044 ZN Zinc Anti-Seize part # 233507 This is one of the only zinc anti-seize I can find. Would this be high on your list for spark plugs? If yes or no…pls let me know why Would it be temp tolerant for plugs? If not this composition…then what and why? Much thanks!!

One interesting ,unusual but IMO very objective way of controlling the proper tightening of spark plugs is by measuring the thickness of the sealing washer . It’s found experimentally that for Denso plugs it must be 1.6mm after proper tightening . Also this method allow you to see if the spark plug has been tightened properly previous time . Also you can torque down your spark plugs dry as the manufacturers recommends . After that remove them ,apply anti seize and tight them back by turning on recommended by the manufacturer angle but for spark plugs which already been tighten at least once .It’s usually stated on the box . IMO anti seize make more difficult to read the proper heat range of the spark plugs which has been in use.

I have a question I replaced NgK plugs on a Gen3 Prius I applied I light coating of Mobil 1 oil to the threads I did not use a torque wrench But i was careful not to over tighten using my best guess Should I have concerns? Was applying oil a bad move? In your opinion should I pull the plugs and do a do-over? Thanks in advance!

I will be the thorn on the side. I never used anti seize. Well a few times but those that had that on them always caused a removal issue. I always chased the threads and thats it. No problems. To clarify, i worked only on mercedes vehicles and used bosch sp plugs.

My 2011 Ranger XLT Supercab 2.3 4 cylinder Duratec has 196,000 miles. I bought it at 60,000 miles. I’ve never replaced the spark plugs. Aluminum block and head. Any advice on removing the old plugs?

Important to lower torque when using anti-seize.

I agree to the difference between dry and lubricated torque, but the torque value tipycally is around 18 foot pound which es a very low value to break a spark plug, on top of that, Champion know about spark plugs because they make them, they make and recommend graphite based thread lubricant and I guess they take that in consideration, on the other hand it is a type of dry lubricant.

This is backyard engineering. The NGK sheet just said to not use antiseize on its coated spark plug threads. Debating this is just like debating the opinion of your old family doctor. Always go with the best authority available and not with your personal opinion.

I don't find any need to use anti-seize in cast iron heads but I do use a light coating in aluminum head. Not sure how anybody can get a torque wrench into some of these tight areas, I've never used a torque wrench but I will say they only need to be tight enough to seal and stay put. Not sure why people over torque them, avoid doing that! I advise against using copper based anti-sieze in aluminum heads due to incompatability between aluminum and copper.

I've never had trouble removing spark plugs I've installed! Torque applied? Simply my judgement as to how much is enough! Never had a loose spark plug either! It's called mechanical feel! Some of us have it! Yes I apply copper grease.

Hello, So…if the friction coefficient of an anti-seized thread is equal to a zinc coated thread, would one torque both the zinc plug and the anti-seized plug to 7 and not 10?

You bring up an interesting point, I just changed My spark plugs, My recommendation for torque was 15-20FT LB I lightly coated all the threads into the cylinder block. Question, am I right in doing so? Thank You

Would Molybdenum disulfide paste be safe and effective?

Spark plugs are grounded through their threads. Conventional anti-seize is a poor conductor, and increases the resistance of the plug, thereby reducing the voltage at the electrodes. If you use anti-seize on spark plugs, which I do, be sure to use the special spark plug anti-seize made by Champion, Unison or ATS that maintains the good ground contact through the threads.

Well, I have never in my life….and that covers a total of 71 1/2 years now and for ASE master certificates… used a torque wrench to tighten a spark plug. I gently tighten using my hand and wrist choked up on the top of the ratchet, so that I am incapable of overtorquing the plug. I’ve never had one come loose, and that spans engines from Farmall tractors to race cars. Now perhaps in recent years, it has become popular to use a torque wrench for spark plugs, and I can definitely see how you could over torque a plug, if you have anti-sieze compound on the threads, and you use the same torque value.

I would use a copper-based anti-seize on spark plug threads for the improved electrical conductivity to maintain the ground strap electrode at zero potential.

Torque could not use on greased fread

I don’t think the zinc acts as a sacrificial anode, zinc is also a lubricant. I have always used anti-seize and will continue to. Never ever used a torque wrench.

But how much effort are you putting on tightening. You can either use a torque spanner if you feel that necessary or tighten until you feel the sealing washer start to pull up. This is no worse a problem than tightening bolts into aluminium. I would suggest the problem will only result if you do not service at required intervals or you are in a marine environment which will have its own servicing time an procedures.

Might be a silly question but, how does a well lubricated plug torqued to 10 ft. lbs differ from a completely dry plug that is torqued to 10 ft. lbs? I can see that the lubricated threads could/would turn through more of the threaded well but both would be torqued to the same specs no? Thanks for posting.

Anti Sieze on any spark plug in aluminum heads for me. Been using it for 50 years, and will continue.

ive never seen a new black spark plug. They have always been shiny.

What about using graphite or "ceramic" compounds?

Anti-seize acts like a lubricant, you have to reduce the torque about 20 percent or run the risk of breaking the plug, bolt, nut, etc. or overthighting.

i use just a dab I have seen too many people just smother the threads with anti-seize, dielectric or just plan grease .to the point of rediculesness covering even the electrodes. than wondering why the plugs are fouling, almost the same as plugs v patches a few years back they tell you not to plug but patches don't galvanize like they used to since doing away with lighting I have used plugs for over 30 years, and they work. Unlike taking down a tire going through all the steps checking re checking only to have that same tire go flat. Two feet from the shop

The list is in order of nobility, if you put any two metals together, the metal higher on the list will be the one that corrodes and potential rate of corrosion is greater the further apart they are on the list. Copper is better than nothing even though the alloy of the head would lose to the copper, its far less than to the iron of the spark due to mitigation of electrolyte by the copper past, that then gives basically 100% protection by there being no medium for electrons to transfer through. Zinc loses to both iron and alloy (the sacrificial anode) and the coating is applied thick enough to last the average duration a plug is in service. As for torque, because of the exact reason you say "less friction" would cause over tightening, spark plugs have a tightening procedure! Depending on the seal face of the plug, flat, tapered, crush washer or flat washer, you turn the plug down by hand till firm then depending on the type of seal, you continue to tighten trough a specified number of degrees.

How would one know or be sure its "30%" less specified torque? Isn't this number dependant on the amount of anti seize a person uses on the plug?

I guess I was lucky? I have a 2001 GMC Yukon that has over 300000 miles on it, the plugs were original! Why it still ran I don't know??? I was able to remove them, it wasn't that hard I was afraid I would snap a few off in the aluminum heads, the only difficulty was the rear plug locations, they were definitely worn down over twice the gap they should have had. I replaced them with IRadium plugs with a dab of anti seize. I think I'll be good for a while now. If you wonder why I am spending time and money on a 21 Year old with over 300k on it? It has absolutely no rust and the engine runs fine. I use it for long trips 3000 miles regularly, I think the highway mileage is what kept it running so long. And I don't beat on it like too many people do to their vehicles today.😮 Treat it like a lady and she will treat you right.

There are some people who should not be allowed to be a mechanic. Just like some people can not be a musician. I have been using anti-sieze for 50 plus years on spark plugs. It is for the next guy. Be sure to use nickel anti-seize not copper. Nickel has a higher operating temperature. Be sure to use it sparingly on the threads. Use your finger to work it into the thread evenly. Start One or two threads back from the electrode end the full length of the thread. This is a great video to educate people on the subject. Trial and error is the best teacher in the long run. If it works for you then don’t fix it. 50+years of experience doesn’t mean you know everything but it does increase your odds of success in this ever changing world.

What do you recommend to use removel of seize spark plugs for my 2004 Ford Expedition

Anti seize on spark plugs is just a bad idea in general. I've been a mechanic for the last 10 years or so. I used to actually use anti-seize on certain engines with aluminum heads. But the problem I started running into, I would torque the plugs to spec, plus a couple extra percent. However, the intense vibrations from a running engine, often the plugs would lose torque and slowly loosen up. Especially on some Ford's, I started to notice when the cars would come back, the plugs would not even be hand tight anymore, you could reach in and spin them out by hand. I recommend changing plugs every 50k miles at the most, regardless if the service schedule says they are good for 100k or whatever. If you just change them more often, it's less likely they will become seized in the holes over time.

do ac delco iridum spark plugs have the coating