You haven’t gotten an answer yet in this thread?
I was mostly responding to the suggestion that adding a quart of ATF to the converter was the solution to the problem.
What Oil Type To Protect Catalytic Converter?
- Thread starter Nessism1
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I was mostly responding to the suggestion that adding a quart of ATF to the converter was the solution to the problem.
The phosphorus limit was only enacted in light ILSAC grades at first because they were the ones that had poor volatility (as well as led to oil burning from insufficient deposit prevention).
Protection must always be though of in terms of risk. High protection against a non-issue can itself be a form of risk if resources are constrained.
The 800ppm limit came in 2004 with API SM. Before that it was 1000ppm as of API SJ in 1996.
Did we have big problems with catalyst failure before 1996 when phosphorus limits were entirely unregulated? I don't know, I was just a college student then. But as a car guy I'd never heard of a bad TWC at all.
The 40 grades being non-ILSAC were exempted from the 800ppm limit until API SN in 2010. At least if they had no diesel rating. It wasn't until API SP that dual-rated (diesel and gas) oils were required to adhere to 800ppm in 40 grades.
So if this was a burning issue of catalyst health, why did API take over a decade to take action?
Let's explore this from another angle. Did European cars have TWCs in 2002? 2006? Of course they did. Hundreds of thousands of European cars shipped with TWCs and a requirement to use A3/B4 or A3/B3 oil-- which has never had an explicit limit on phosphorus. Now, is it likely that a European OEM would accept warranty and potential regulatory entanglement on so many vehicles if there was any significant risk to the catalysts from using an A3/B4 oil?
Even ACEA C4 allows 900ppm Phosphorus, and this is the ACEA version of "low saps" oils with a max total SAPS of 0.5%.
I just don't think there's any real risk to catalysts whatsoever from the higher 1100-1200ppm max of some A3/B4 oils. The risk is from oil consumption, not from phosphorus content. Thus my prior post: if you are guzzling oil, no phosphorus level is low enough to save your cats. And if you have little to no consumption, then no A3/B4 oil has enough phosphorus to cause a problem.
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I might be saying something very stupid, so feel free to correct me, but the smog test usually doesn't involve putting a sniffing probe and analyzing actual cat efficiency. All it does is check the OBD info for errors and codes and "cat preparedness" or whatever that chain of interlinked sensors and gizmos that have to all report that they are doing good.
So if you have a high mileage vehicle things such as fuel delivery issues that would trigger check engine lights downstream will be much more concerning than whatever type of low quantity oil your engine burns. As mentioned above, should your engine become an oil burner, it would cause harm in the long term as well.
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OVERKILL
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40 and 50 grades are both still exempt, that's how Mobil 1 Full Synthetic 0W-40 is API SP and 900ppm of phosphorous.
Ah, that's right. Thanks for catching.
OVERKILL
$100 Site Donor 2021
It's not conflicting, as I pointed out earlier:
- API has low (15%) limits on volatility (Noack) and quality standards aren't overly stringent (hence Dollar General quality oils being SP or SQ)
- Phosphorous restriction was imposed on xW-30 and below (the ILSAC grades) which were more likely to end up being consumed and would be more likely to have increased volatility, bringing us back to Noack.
- Euro oils have stricter limits on Noack (typically 10% or lower) and the OE approvals are generally more stringent.
- Euro oils have to jump through more hoops for emissions protection (GPF/DPF protection) than API, but have higher permitted phosphorous because the approvals result in the oil being less likely to end up in the exhaust system.
For older vehicles, they shove a probe up the tailpipe. Then the car is run on rollers, so they can check HC, NOx and what have you.
Lowest saps possible. I know delo adf is 0.4% but pricey for what it is but a 0.8% saps oil also helps.
But saps and emissions matters if the oil is being burned. So if there's consumption that'll be the root cause of emissions issues no matter what it is though higher saps will cause issues faster.
Though bad spark plugs lazy maf and 02 sensors can also increase emissions which is why some owners manuals like on the mitsubishi say that sparkplugs are an emissions item that have to be done likely because the engine would still run good enough to not merit them being changed but would create more emissions and could cause it to fail emissions. I know there's nox and co2 and it's possible to reduce nox which i think is what's tested harder. Fine twin tip ruthenium or iridium plugs like in ngk or densos are known for propagating flame kernels faster and reduce emissions and increase performance. I know i've seen a graphic before on rock auto when looking for parts i'll try to find it.
Don't think i can post the thing so here's the link. I switched to fine point ngk plugs on my ope and they all fire up easier and run better.
https://www.rockauto.com/en/moreinfo.php?pk=6276849&cc=0&pt=7212&jsn=3
But saps and emissions matters if the oil is being burned. So if there's consumption that'll be the root cause of emissions issues no matter what it is though higher saps will cause issues faster.
Though bad spark plugs lazy maf and 02 sensors can also increase emissions which is why some owners manuals like on the mitsubishi say that sparkplugs are an emissions item that have to be done likely because the engine would still run good enough to not merit them being changed but would create more emissions and could cause it to fail emissions. I know there's nox and co2 and it's possible to reduce nox which i think is what's tested harder. Fine twin tip ruthenium or iridium plugs like in ngk or densos are known for propagating flame kernels faster and reduce emissions and increase performance. I know i've seen a graphic before on rock auto when looking for parts i'll try to find it.
Don't think i can post the thing so here's the link. I switched to fine point ngk plugs on my ope and they all fire up easier and run better.
https://www.rockauto.com/en/moreinfo.php?pk=6276849&cc=0&pt=7212&jsn=3
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Metallic additives supposedly. But if your not burning oil then it's a non issue.
None-zero is my point. OP asked for oil to help with cat life. Delo 600 is the best he can do. It does not have any API spark approvals. Others recommend the ESP 0w-30 which does not have any either.
4wd
$50 site donor 2026
Yep, based on counties in many cases …
Why would you call an oil Emission System Protection (ESP) that is run in modern expensive cars, if it harms the catalytic converter?
One reason the former version of the ESP oil was not API certified is because it was exclusively made for the European market, where people look for the ACEA certification, not the API one.
The current version mentions API SQ on the label (image on page 1).
It's not certified API, but it meets test specs.
OVERKILL
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It's API SL, which was the last API certification that an oil in the xW-30 and below grades could carry with more than 800ppm of phosphorous. This is interesting, because Mobil's own phosphorous levels sheet shows it at 800 nominal, so right on the line, while the 0W-20 is 880ppm, so clearly non-compliant.
It still oil made specifically for the European market. Mobil just decided to sell it in the US as well because it's a well designed oil at a great price. Not going to change the label and certifications for that though because the US is a secondary (the least) market.
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OVERKILL
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I wouldn't say European market, more European approvals. It's designed to meet the performance requirements of Euro OE approvals (MB/Porsche/VW) of which there are many applications for sold all over the world, including here in North America. They slap the API designation on it because they can self-certify for it, so it doesn't really cost them anything, and it probably gets them additional sales.
O.K. Let's say it that way.
However, the ESP oil is sold in Europe initially (like 15-20 years ago or more) and then brought to the US, the last 7-8 years or so.
It might be available a bit earlier here, but only at boutique oil stores, not Walmart, AutoZone or AAP.
Before that, people were driving German cars with Mobil 1 Euro 0W-40.
OVERKILL
$100 Site Donor 2021
GPF's and DPF's were the main driver for the mid and low SAPS (ESP in Mobil parlance) oils, and yes, there's that distinction because we didn't get those things (and still don't have widespread GPF use) on this side of the pond until much later. So an engine that called for a mid or low SAPS lube in England might call for a full-SAPS lube here.
That said, 7 years ago is 2019, lol, and we have had these oils a lot longer than that. Here's a post from @edyvw in 2014 when he was using ESP 5W-30 for example. Here's another post from 2011 about a guy switching to ESP in his Touareg, so that's 15 years right there.
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