Join the conversation on the new forum! lubrication.expert/forums - it's free to sign up and start contributing.

The first time I read an article about ZDDP was about 20 years ago. The article was on the subject of what affects the removal of ZDDP from Motor Oil would have on those people who owned classic cars that were built around the 1950s and 1960s. This was because cars of that era had flat tappets that would slide on top of a rotating camshaft. And that on those engines the ZDDP prevented excessive wear of the camshaft and tappets from occurring. The article also covered the use of ZDDP additives for classic cars that did not have catalytic converters. Basically ZDDP was removed from Motor Oil to prevent fouling of catalytic converters.

Catalyst: Wonder if trees think CO2 is "pollution."

Father was a 32 year machinist of old technology. He swore by STP zDdP Because of its ability to do what it’s best at.

Zddp makes my car engine super smooth ..love it

I don't know why this appeared in my suggested videos but I found it very interesting and I have now subscribed

Seems that industrial applications would be better served by paying attention to heat management in the oil. Instead of just letting oil temps get out of sensible ranges and then demanding a new oil spec.

ZDDP breakdown at 110-120c is very relevant to car engines which see heavy use like in race cars. It's not unusual to see engine oil temps to 120, particularly if no cooler is fitted. Thanks for that info.

This is a brilliant explanation of not just ZDPP but also the significance of using the right oil. I run classic cars through to a 2022 tractor and 4Wd. Each has specific lubricants and what's good in a 70 year old classic would be extremely unwise in a modern diesel or petrol vehicle.

Subbed to the channel. I'm an ex motor mechanic who is now in Underground mining maintenance and planning. I have no formal training in the lubrication industry, but have built a some knowledge over the years. I also have an unhealthy love of Enduro dirtbikes and try to share good information with other bike owners regarding their lubrication choices. Great to see some in depth content on KZfaq 👌

I live in Florida where it's always "hot" and learned about synthetics and zinc in 1995, ran a lawn service and use 15W-50 synthetic oil (Mobil-1) plus one quart of synthetic "diesel" for the added zinc. Annual oil changes in vehicles, 2X annual in commercial lawn mowers. No cat plugging or emission problems in hundreds of thousands of miles, however we don't have emissions testing here. No lost motors from wear, except 1 "pawn-shop" edger motor that may have been on it's last leg - seized up a piston. Mercury outboard 2-stroke run at 100:1 on AmsOil, I was giving all my 2-stroke motors a shot of the "zinc" Diesel oil periodically. Same oil in motorcycles with the "zinc-Diesel" except one ended up with a slipping clutch at 32,000 miles, so a clutch-swap with a parts bike and different oil for that one. The oil was too slippery for the clutch to grab! But still ride-able. Engines - Chevy 305 and 350, Dodge 360, Chrysler 2.7, Chevy 5.3, Honda 500, Yamaha 750, 900, 1100, 1300, Kohler, Kawasaki, Briggs & Stratton, Stihl, Echo. Mercury 40, Mercruiser 135HP.

your teaching is beyond exception. Top Score my friend

Just a layman who enjoyed and appreciate this content.

I have an old 2000 4runner that specifies API service SF 5w30. Being that modern API standards are intended for vehicles with roller valve trains and do not have the same levels of anti wear additives, I have been using off the shelf 5w30 full synthetic also adding a ZDDP additive on oil changes.

I have collector cars. They require ZDDP in the oil as it was standard in the oild they were designed for. Now I have to add it every oil change. This is a kick in the b@lls for collector car enthusiasts.

Good video. I will say though that ZDDP is still widely used in any non cat engine oils like small engine oil, marine, motorcycle, racing oil etc. That's why you should always use the oil with the correct classifications for your engine.

I have definitely seen zinc causing issues in hydraulic systems. Interestingly enough when we transitioned to a low ash, zinc free synthetic hydraulic oil, the varnishing issues didn't decrease over time, even with more stringent filtering regime. What we found was the synthetic oil had such low conductivity that static discharging through the filters was breaking down the oil and forming varnish. The black discharge marks were really visible in the filters which helped us identify it.

Carbon dioxide is still a harmless inert gas.

Good video. Thanks for the time that you put into this. My Machine Shop is a Engine Shop. So you can see why I would be into ZDDP. I just subscribed. 👍 Take care, Ed.

Hey.... Nice video, matey. Kudos on explaining a complex topic in terms a lay person can absorb. P.S. Greets from Perth.

Wow so glad to find this channel!

Thanks, very interesting. People don't realize the importance of lubricants. There are some very exotic lubricants I am aware of that offer some unique qualities and are sold to airlines, railroads, and major industries that can afford it, to see an economic benefit. This is something the regular folks would love to have in their passenger car but the expense that make it prohibited.

Excellent video, I was interested in the science of water retention in ZDDP, Moly also shares some of these problems. The heat degradation...very interesting..thank you

Thx for your knowledge 💪🏽

Fascinating

Nothing makes me sadder than when a well loved compound goes to the great chemical refinery in the Earth's mantle. Tears are falling into the keyboard as I type this.

That "NEW" additive compound is indeed here. Petroleum Sulfonate EP

So, if I'm following you, ZDDP for transmissions and differentials should still be OK, because 1) their operating temperatures are much lower, 2) there's no catalyst to foul, and 3) they aren't sensitive to sludge like solenoids. Is that correct?

As someone who does not live in an area of the world which requires emissions equipment and someone who is actively involved in disabling his own emissions equipment, I have no concern for the lifespan of a component which will be removed soon if not removed already. I will use as much Zinc as I like in my engine oil and there is nothing anyone can do to stop me. I will single handedly warm the earth.

In the U.S., ZDDP has been on the chopping block for years. Since the early 2000s, all road engine oils have had massive cuts to ZDDP content (or any other solid particle based additives). ZDDP usage is largely limited to aero engines and large marine applications (freight ships).

Super interesting!

If it is, it will be the end of classic engines too.

What happens to all the small engines out there that still need zinc in the oil? It’s not like OEMs can easily and cheaply redesign all their engines to use roller valve trains. As someone who has been involved in the industry for a lot of years as both a mechanic and shop owner, this is going to be a major headache going forward if zinc is removed from all engine oils.

So if ZDDP builds on a surface to make an anti-wear coating why is it not wanted in industrial transmissions or automotive manual gearboxes? In the 1980s I worked for a bus company that ran interstate express vehicles that clocked up an average of 30,000km per month. We were using spicer 7-speed crash boxes and were getting quite a bit of metal showing up in the oil testing after the 500,000 km mark. Our lubricant supplier felt that the boxes were sucking in dust or dirt as they were at the rear of the vehicle but silica readings in the lab tests did not bear this out. We had a contractor working for us with a vehicle that had just passed 500,000km and he used a different brand of oil so we lab tested his oil and found much lower metal in the oil. He was using molybdenum di-sulfide as an additive in his gearbox. We set up a test where the next two vehicles delivered new were sampled every two months with one vehicle having the additive and one not and the results were the same as the contractor's vehicle. The reason for it we were told by the additive supplier was that it built up on the mating surfaces and formed and kept metal surfaces apart better. So again why would you take out ZDDP if it would do a similar job? We started adding the Molybdenum to all the vehicles and we pushed out the gearbox rebuild Ks to 800,000.

Hexagonal Boron Nitrate and Tungsten Disulfide can be used to replace it and "Moly".

Great video & full of great information

@lubricationexplained love the channel, and found it by this video. Would you be able to talk about some EP additives that are replacing ZDDP. Maybe even talk about TCP, as in found in marvel mystery oil.

It will be around forever, it's like leaded fuel, you can still buy it. I can buy a drum of leaded or a drum of 116 E85 it's all for sale just not at pumps. Same with ZDDP oils if you look you can find them. I just tend to use what the oil company we use recommends and stick with that. I'm in Automotive and I have not has any issues using what oil companies recommend, apart from semi synthetic oils which I despise using, we rarely buy in full mineral oil so I can't really comment on those for engine use. The semi synthetics always seem to varnish the inside of the engines partly due to customers doing 10k or 15k intervals on semi synthetic when the oil tech line states to do the adverse condition intervals at 7.5k with semi. But yea when using full synthetic oils in engines they run fine, but most engines these days use rollers in the metal to metal contact areas. My 2.6l Triton 4G54 uses an OHC with wiper rockers and was re-built 40k ago, I use Penrite 15w-40 but it's extra 10 so they claim it's a 15w-50, it's full synthetic but I think it has ZDDP in it I'm not sure but it runs fine.

most interesting ... thanks a mint for this tutorial

So basically because the government's crusade on cheap affordable energy is leading to the end of an additive that is basically perfect. Sounds great for manufacturers who benefit from early engine failure.

All I know is 20 something years in the construction heavy equipment demolition tree and Grading etc etc etc most folks run Rotella oil and the motor is just run and run and run and run

I've always been skeptical about the practicality and efficacy of ZDDP & other Zinc additives in oils. The idea of there being tiny metallic particulates in oil made me imagine the possibility of the Zinc building up in orifices among other places where it doesn't necessarily need the potential 'benefits' ZDDP may offer. I'm glad someone with a better understanding of the chemical/molecular break-down and processes was able to prove my skeptical cynicism wasn't completely unwarranted lol. Appreciate the input!

I could understand well about ZDDP. Thanks 🙂 Could you explain the mechanism in more details about what you said that the metal containing additives tend to hold on to quite a lot of water??

Fk em. Oldtimer engines with flat tapped cams need it, and I WILL use it.

Outside of catalyst fouling, are there downsides to adding ZDDP in modern engines that weren't designed to require it?

So in other words, us classic V8 muscle car guys should think about ditching flat tappet camshafts for steel roller cams? There is a lot of evidence of increased failure rates of flat tappet cams and lifters, and attributing it to "chinese steel/iron" being softer etc etc - or is it that the break-in ZDDP additive package needs to be in EVERY oil change - not just the cam/lifter break-in cycle fill ? Great video, thanks💪 Subscribed🙏

Cam mnufacturers will have a MAJOR problem with this. They specify zinc in the oil or will not warranty a cam.

This caught my attention because I noticed that zinc has been removed from denture cream. Why? I don't know. I know it's not healthy when using that cream for dentures over long time. I saw this and thought there is a relation from zinc being removed from this product as well as others and am wondering why the push to remove all the sudden.

Do you think new engine oil specification GF-6A with less zinc will provide the same engine protection as old engine oil specification ACEA A5/B5 with zinc?

I wouldn't worry there. There are oil manufacturers who specialize in oils with a high zinc content. And as long as the demand for classic cars and racing vehicles in particular is high, there will also be suppliers of oils with a high zinc content in the world.

Really interesting!! I thought oil was just ah oil that lubes and removes heat

Sort of…. The load creates the film. ZDDP remains in suspension until a load is applied, forcing the ZDDP to bind to the base metal. Without a load, no bonding occurs

I would be curious to hear your opinion on what is contributing to camshaft failure (where the lobes wear off) in bucket lifter applications such as ford and nissan etc gas engines.. do you think it is related to the reduction of zddp in oil or perhaps poor manufacturing of the camshaft? Or something else?

Since motor oils are generally backwards compatible, I wonder what modern chemistries they’re using in place of the old ZDDP?

Blend your own oil, or buy Redline or Schaefer’s or ZDDP additive

Can my 2005 toyota tacoma prerunner truck use oil without this or is my truck new enough to use the new standard oil.

Very interesting video! I've got a 2021 Jeep with the 3.0L EcoDiesel that has a normal operation temperature of about 230 degrees F (110 C). The manual says I need to use a 5w40 Synthetic oil meeting API-SN and Material Spec MS-12991. My understanding is that an "API-Sx" classification indicates an oil for a gasoline engine versus an "API-Cx" which is intended for a diesel engine. Do you know, or have you already done a video that discusses why a diesel engine would specify a gas engine oil?

I would not panic ZDDP is going nowhere in the near future. It is so heavily used in hydraulics and engine oils. It is relatively easy to make and manufactured all over the world. The real key is that 50% of the world's engine oils are below API SN so use high levels of ZDDP. Industry has had zinc free products for decades, often for technical reasons and many diesel trains have always been zinc free due to silver bearings. Industry has not got rid of chlorine additives with long chain chloro paraffins still in use, and that was a major drive 20 years ago successfully removing short and medium chains but the element chlorine is still an issue in disposal. The drive will always come from the consumer side, electric cars do not have to use ZDDP for example. The ironic thing is that cresyl phosphate esters are the common replacement and they have such a poor environment profile that above 1% potentially label the entire lubricant as environmentally hazardous.

I'm sure ZDDP wil be produced for quite a time just to make hotrodders like me happy

Catalyst have been mandated on cars in the USA since 1974, 20+ year before the zinc debate. The old cars (before 1987 ish) had flat tappet cam shafts that depend on the zinc, without the zinc, cams can wear out in under 1000 miles. So why did they take out the zinc? The EPA pressured the oil companies to do so sole because the zinc in very high milage cars "Could" have their O2 sensor become inoperative if the zinc built up from blowby. Clearly it caused more problems than is solved, or maybe it was part of a plan.

I think molybdenum disulphide is an incredible anti-wear additive!!! I swear by mos2 !!!

Reason I use Puröl oil is high zddp and moly

Great explanation . Is it true ores rumor that ZDDP is aggressive to oil seals especially shaft seals ? Thank you for your help.

So I've been trying to find a lubricant for my 3D printer linear rails, they use roller bearings. Have any thoughts on what oil/grease I should get? The rails are horizontal and vertical.

Zinc is good

Air-cooled engines operate at a lot more than 110-120C. Does the ZDDP break down in those? Air-cooled engines certainly have shorter oil change intervals than water-cooled engines and generally don't last as long. :-)

I own two 80s Nissan gas engines and run Rotella T4 diesel oil in them because of the yellow friendly zddp.I dont think it will hurt a 36 year old catalytic converter? I learned to do this from the internet so any experts here please let me know what you think.

hopefully rotella doesnt stop adding zinc.

ZDDP kills catalytic converters are urban legend than facts. Low quality oils easily evaporates allowing the oil vapers into the cats. That process still takes years to clog a cat. I use a ZDDP Additive (Redline) and use a 2100 PPM Mix (Valvoline Advanced) on my twin turbo application with zero issues. Mean while Ecoboost engines get a bad Rap. ZDDP is critical for Turbo Protection and massively reduces the oil from coking.

i'm recently hearing of zinc in oil. i'm confused as to what i should be doing. i have a 86' GM car BUT the engine is a brand new 350 sbc crate engine a reproduction for 87 - 95 HD trucks with hyrol flat tappet cam with maybe 1400 miles on it. next oil change will be 10w 40 synthetic, should i be adding zinc? also i do have cats (that i don't care about).

My Grandfather Worked for Texaco His Entire Adult life, Except for WWII, and Korea. After Returning from Europe @ the End of WWII Texaco Sent Him Back to Collage for an Engineering Masters Degree in Lubrication. Where He Did Both Lab ( Prototype formulations & Field Testing, Pre- production with Commercial Accounts ). Unfortunately During the OPEC Oil Embargo Some Braineaic at Texaco picked An arbitrary age range and anybody younger or older than the bracket was either fired or retired depending on where you landed and my grandfather was retired and that just broke his heart and my grandfather was one of those while he was the greatest generation just took just his vacation and never called in sick but unfortunately was that age range where it was impossible to get rehired and that was it but when you would tell me the stories of what they would do to test new formulation was incredible and later when I was getting my A&P license we had a lot of World War II fighter pilots and bomber cruise that were instructors and what they would how they would fly their planes after getting the s*** shot out of them and that correlated a lot to the experiences my grandfather had working at Texaco with testing new oils and let me tell you it's amazing what just a little bit of film in an engine can do if you're just a little easy on the throttle.

ceratec addative from germany works great, and usa made restore addative work great also.

My question is, how much is required and how to assess what is a reasonable level ? ZDDP is sacrificial in action. Will low levels provide protection for a short period of time, of if high pcontact pressures exist is a high % required from the start. Lots of unanswered questions on this subject and few hard fact vs hype from specialty product manufacturers hoping to cash in on owners fear.

Your videos are excellent! Question: besides the moly analogue, are there currently replacements for ZDDP that solve the problem of catalytic deposition? Maybe a package of several different compounds to separately participate in the three regimes of the anti-wear coating? For the Fe/Zn regime, I was wondering if there could be a substitute that doesn’t have affinity for the Pt/Pd/… catalytic metals?

Has "Restore" engine restorer crossed your radar? It claims to restore compression, and seems to be the only product that has been verified to do so, sometimes dramatically. Contains various soft metals. I cant seem to find any real info on it or long term effects.

Is high zinc also bad for o2 sensors? I heard somewhere that using too much zddp increases friction, I use archoil, dont know what's in it but it seems to be good stuff

Do you have any videos that talk about the new DEXOS 1 Gen 3 spec? It looks like it has a much better additive package for turbocharged engine. Other than that it seems very similar to Gen 2

How does the Rotrex oil work? The brochures say that the oil "momentarily" increases viscosity under high load.

The question is what will it take to make up your own at home.

Hello, I currently use a Zinc-free hydraulic lubricant in a Sacmi press, when carrying out lubricant analysis and noticed that sample after sample the Zinc trend is increasing, we have already ruled out fillings or additions with other types of lubricants, I ask, what Other possible ones exist to generate this increase in the trend of Zinc. Thank you!!!

Come back Zinc, come back! -Jimmy

what is better technology as compared to zinc if you want to replace it?

Pls provide the link for the magazine

You mentioned right at the end that new better lubricant additives are coming. Have you taken a look at XcelPlus which acts as a boundary lubricant but with none of the downsides of ZDDP? 🙂

My flat tappet cams tell me you’re a decade too late. Please try again

Zinc is a flat tappet cams best oil additive .

should i use an additive for my non catalyzed flat tappet engine?

You threw me for a loop as what is the relevance of ZDDP in gear oils to catalytic converters? Neither my manual transmission or differential / third member vent through a catalytic converter.

what are the substitue for zddp? is there any substance enhance motor power output same as zddp? mos2? boron?

Question is should I add ZDDP to my engine oil? Newer cars, say the wife’s Macan Turbo (damage cat?), my 2020 Triumph motorcycle (no cat), my 74 Norton, … 71 911, … 2006 911? And the list goes on!

What are the “better technologies” out there?

ahh, so the steel mills don't sell it off anymore. interesting.

So does ZDDP Ruin a catalytic converter? Can I just buy it on Amazon and add it to my oil?

So why do car manufacturers don't control oil temperature so it stays below 100C?

Liqui molly Special Tec F 5w30 has a lot of zinc. Actually i use it in my mazda and the oil works great. It is way quiter than Special Tec AA which has boron and Molybdenum. And it is a pretty modern HC oil still sold in Israel.

What are they replacing ZDDP with?

Some motor oils are using titanium as an antiwear additive. Is it any good ?

i classify oil as coolant then it ok to drink

What is going to replace ZDDP then? Why will it be replaced? Simply because of emissions?

So when Liqui Moly Ceratec and Mos2 are said safe to catalytic converts. Is it a lie?