ZDDP concentration in Amsoil Zrod oil

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I don't see the zinc levels listed on Amsoil's website. I downloaded a technical file (g2883.pdf) that states in several places that it has high levels of ZDDP, it has a table that shows about a dozen parameters but NONE OF THEM are ZDDP concentration.

Why not?
 
I don't see the zinc levels listed on Amsoil's website. I downloaded a technical file (g2883.pdf) that states in several places that it has high levels of ZDDP, it has a table that shows about a dozen parameters but NONE OF THEM are ZDDP concentration.

Why not?

You might need to buy a quart of this Oil and get a VOA done. A VOA is gonna go farther than Amsoil's advertising that this oil is high in ZDDP.

There is a VOA of this oil on this site, but it is from like 2012!
 
I don't see the zinc levels listed on Amsoil's website. I downloaded a technical file (g2883.pdf) that states in several places that it has high levels of ZDDP, it has a table that shows about a dozen parameters but NONE OF THEM are ZDDP concentration.

Why not?
Paging @Pablo ……
I might add, the Amsoil Zrod oil is held in high esteem in the Fiat 124 Spider crowd due to its high levels of ZDDP.
 
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I don't see the zinc levels listed on Amsoil's website. I downloaded a technical file (g2883.pdf) that states in several places that it has high levels of ZDDP, it has a table that shows about a dozen parameters but NONE OF THEM are ZDDP concentration.

Why not?
ZDDP is an ester consisting of three elements, Phosphorus, Zinc, and Sulfur.

The ZDDP elemental averages in ZROD are Phosphorus - 1350ppm, Zinc -1425ppm, and Sulfur - 3800ppm.
 
I'm watching this video:


It's an analysis of Amazon Basics Euro 0W-40 from earlier this year. It has 1242 PPM Phos, 1327 PPM zinc. Are those levels appropriate for flat tappet engines? (don't know about the S or how important that is)

I'm under the impression that any oil that has enough Z and P for FT engines was bad for cat convertors.
 
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1200-1400PPM
ZDDP is an ester consisting of three elements, Phosphorus, Zinc, and Sulfur.

The ZDDP elemental averages in ZROD are Phosphorus - 1350ppm, Zinc -1425ppm, and Sulfur - 3800ppm.

Those numbers are almost exactly the same as Mobil 1 15w-50, numbers which Mobil does publish. The M-1 15w-50 is used by many classic car owners, and has the advantage of being well priced.

Z
 
I'm watching this video:


It's an analysis of Amazon Basics Euro 0W-40 from earlier this year. It has 1242 PPM Phos, 1327 PPM zinc. Are those levels appropriate for flat tappet engines? (don't know about the S or how important that is)

I'm under the impression that any oil that has enough Z and P for FT engines was bad for cat convertors.

Mobil 1 0w-40 F/S has somewhat elevated zinc (1,100 ppm) and phosphorus (1,000) ppm, and is being used without issues in my flat tappet classics as well in my catalytic converter equipped 2002 Jaguar XKR.

Z
 
My random example of Amazon Basics Euro 0W-40 seems to have high levels of Z and P (don't know about the S). If an oil like that is sufficient for FT engines, then is that oil targeted for classic cars with FT engines? Can an oil like that be used on regular cars with cats? If the answer to both of those questions is yes, then I must be wrong about oils with high ZDDP (oils for FT engines) being bad for cats. So why did they reduce ZDDP in the oil over the past (30?) years if it's ok for cats?

(bit of a side issue but I'd rather use a 10w30 than a 0w40 in a 318).

I'm just confused about whether or not oils with sufficient ZDDP for FT engines are commonly available (or not) and if they are, are they segregated away from the general public if they're bad for cars with cats to avoid people wrecking their cats because they don't know.
 
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My random example of Amazon Basics Euro 0W-40 seems to have high levels of Z and P (don't know about the S). If an oil like that is sufficient for FT engines, then is that oil targeted for classic cars with FT engines? Can an oil like that be used on regular cars with cats? If the answer to both of those questions is yes, then I must be wrong about oils with high ZDDP (oils for FT engines) being bad for cats. So why did they reduce ZDDP in the oil over the past 10, 20 years if it's ok for cats?

Could there be some empirical data that supports a level of zinc and phosphorus that is OK for the modern car emissions equipment ? I don’t know what those numbers would be.

But there’s a lot people on this forum using the M-1 0w-40 F/S in their own cars. Cars which have the full compliment of catalyst converters in place. I don’t recall a slew of failures being reported. So that particular product must be under the cutoff point.
 
How would people know that the cat's are being wrecked? Cars don't have sensors for that, all the sensors are before the cats aren't they? Only a tail-pipe test would tell you - yes?

I didn't think that conventional oils need to have ZDDP any more for the tappets. Why would that Amazon oil have so much zinc?

I've just had a look at amazon, I'm not seeing that oil as being available, but am seeing reviews for it as recent as last week? Is this a diesel oil?
 
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How would people know that the cat's are being wrecked? Cars don't have sensors for that, all the sensors are before the cats aren't they? Only a tail-pipe test would tell you - yes?…

no.

Even my old 2002 Jaguar XKR has both upstream and downstream O2 sensors. A code is thrown if the catalytic converter is not working correctly.

I don’t know about other cars, but doubt a 20 year old Jaguar is the only one that can tell if the catalytic converter is functioning.
 
Can an oil like that be used on regular cars with cats? If the answer to both of those questions is yes, then I must be wrong about oils with high ZDDP (oils for FT engines) being bad for cats. So why did they reduce ZDDP in the oil over the past (30?) years if it's ok for cats?

I'm just confused about whether or not oils with sufficient ZDDP for FT engines are commonly available (or not) and if they are, are they segregated away from the general public if they're bad for cars with cats to avoid people wrecking their cats because they don't know.
Walker Muffler says this:

"Catalyst poisoning occurs when the converter is exposed to emissions containing substances that coat the working surfaces, enveloping the catalyst to the point it cannot contact - and treat - the exhaust. 

Potential causes for coated or fouled substrate may include:
  • Excessive carbon buildup in exhaust
  • Internal coolant leaks (head/intake gasket)
  • Use of non-converter-safe gasket sealants
  • Excessive oil consumption (burning oil)
  • Improper fuels or additives (E85, diesel)?"
The excessive oil consumption could be due to worn rings, worn valve stem seals, or an oil's high volitivity.

An oil with a high volitivity can deposit it's metallic components, such as zinc, calcium, and magnesium and others and coat (poison) the rare-earth substrates that catalyzes the exhaust.

So this was the main reason for reducing the ZDDP content, the calcium/magnesium detergent levels, and decreasing the volitivity spec for new oils.

A secondary reason came from the EPA in its desire to reduce heavy metal content in the environment. But ZDDP still is the king as an anti-wear agent.
 
This was 6 years ago. Yea, something to think about. If the oil isin't burned / evaporated, it's not going to get into the exhaust. Still, why are ZDDP levels going down? Do I really have to spend $60 for boutique oil for my FT engine when maybe there's still 1990 levels of zinc in a lot of oils?

 
This was 6 years ago. Yea, something to think about. If the oil isin't burned / evaporated, it's not going to get into the exhaust. Still, why are ZDDP levels going down? Do I really have to spend $60 for boutique oil for my FT engine when maybe there's still 1990 levels of zinc in a lot of oils?
I just explained why ZDDP levels have been reduced.

I am not sure what your complaint is.

If your FT engine requires an oil with a higher level of ZDDP than commercial PCMO oils, then find one and use it.
 
“…… Do I really have to spend $60 for boutique oil for my FT engine when maybe there's still 1990 levels of zinc in a lot of oils?….”

I haven’t spent more than $30 per 5 qts. for any classic, some valued well over $500k.

1j,990 ppm is a lot, more than any 1950’s-1960’s-1970’s flat tappet engine that I know about needs.
they survive without wear with zinc levels of 1,100 in the M-1 0w-40. And do fine with the 15w-50 which is in the 1,300 ppm range (zinc) and can be had for under $30 for 5 qts.

And you can use the M-1 0w-40 in modern as well as the old iron equally.

So, what’s the problem ?
 
Zrod is formulated for high performance engines with high lift/duration flat tappet cams and high seat spring pressure valve springs. It is NOT intended for OEM engines.

Is your 318 a rebuild? If so, was it built with OEM equivalent parts and specs? Was a new camshaft and lifters installed? If so, was the new camshaft broken-in properly? Does your 318 have cat's?

My 1993 Ford 4.9L (300ci) unopened flat tappet engine is closing in on 300k miles living on everything from API SL (when new) to API SP with no camshaft/lifter issues.

I chose to move to a Euro A3, A40 5w-40 oil for other reason and ZN/PH wasn't one of them.
 
Zrod is formulated for high performance engines with high lift/duration flat tappet cams and high seat spring pressure valve springs. It is NOT intended for OEM engines…….”

In my limited experience I haven’t seen any classic engines, stock or modified, that needed more zinc and phosphorus than what what supplied by Mobil 1 15w-50 (1,200 ppm / 1,300 ppm). Including, but not limited to, vintage Shelby Cobra’s, vintage 911’s, and vintage Shelby Mustangs. All were modified for competitive vintage racing.

I don’t know what higher levels of zinc and phosphorus than that get you in the way of reliability or wear protection.
 
In my limited experience, it has been recommended to not go above 1200 ppm ZN in a street driven vehicle (some say 1600 ppm). Higher levels are reserved for engines that are not required to be daily driven for gazillions of miles. If I remember correctly, the high level of ZN erodes away bearing surfaces.
 
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