How much Zinc and Phosphorus is too much,?

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I've read differing and confusing data regarding zinc and phosphorus...

I called Dave at Redline and he said that it is not zinc levels that cause problems but phosphorus levels....
I didn't ask him how much zinc and phosphorus is too much for passenger cars and light trucks...

I've searched the topic and found that 1400 ppm is too high,,,another said 2000 ppm is too high... Another sight said 900 ppm is high for zinc and 800 is high for phosphorus,,,What is the real story...?

I don't want to hurt catalytic converter ..I have 2008 F-150.. Different oils show different levels of zine and phosphorus...

What is too high and what is too low in terms of ppm for passenger cars and light trucks for zinc and phosphorus..?
Thanks
 
I think based upon what we see for longevity and wear performance, the current levels with the other additive chemistry is more than sufficient.

For high spring pressure flat tappet cam engines, ZDDP sure appears to do well at the lowest price point. But this isnt relevant to modern engines. New and alternate adds work perfectly well, and so Id not be concerned with ZDDP at all at current levels.
 
More and more research is being done in the additive industry and the trend of lowering ZDDP seems to be balancing nicely. I would stay away from high ZDP add packs in your truck, use a high quality API SN lube from a major and you will be protected just fine without cat issues and extra deposits where high ZDP oils can cause those issues.
 
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Use an oil that meets Ford specs for your engine. Does Redline meet specs? Seems like Redline is overkill for many apps, but if it meets the requirements of Ford, it should be fine even if it's expensive. Unless the engine is burning a lot of oil, poisoning the catalyst isn't likely. One of the more common and less pricey oils available at Walmart will keep your engine in good shape for a long time, plus the convenience of getting oil locally. I know there's a certain feel-good factor of thinking we have the best of the best in a certain vehicle, but truth is, there are many very GOOD options for your truck.
 
From what I recall, too much zinc, somewhere above 1500 ppm zddp can cause pitting of the metals inside your engine, including the bearings. For the Cat, they seem to like a very low number but that is driven by the manufacturer being required to warranty the cat for a long time (what is it now, 150,000 miles?). So they would be inclined to be overly conservative. The phosphorus can't poison the cat unless it gets to it. If your engine does not consume oil I would not think it would be an issue. Any of your name-brand off-the-shelf oils are not going to have too much zddp. Redline oil has a lot of zddp, maybe 1500 ppm, not sure.
 
Originally Posted By: [censored
]I've searched the topic and found that 1400 ppm is too high,,,another said 2000 ppm is too high... Another sight said 900 ppm is high for zinc and 800 is high for phosphorus,,,What is the real story...?

TallPaul is right - excessive ZDDP can cause spalling on surfaces, including cam shaft surfaces, and your truck doesn't need it. 2000 ppm is definitely too high and I wouldn't go near that except in a racing application, and 1400 ppm is more than is necessary for most applications out there. I'd probably not be afraid to use a 1400 ppm zinc oil in my old F-150, if one were available in a sensible viscosity at a sensible price. But, I don't need anything near that level, so I wouldn't go on a massive hunt for such a product.

The lower figures you quoted are what you're looking at, roughly, in SN/GF-5 limits. Do not that most SN/GF-5 oils will have somewhere between 700 to 900 ppm zinc, very roughly rounded off. That's more than enough for your application.

Besides, there are some things that you should consider. First, older oils didn't all have these insane ZDDP levels that some people "remember" so fondly. A lot of the oils in those days had similar levels to what we see now when an oil is bumping at the upper limit. ZDDP isn't just exactly one compound either; there are other varieties. ZDDP also isn't the only anti-wear compound in existence, and oils have improved greatly and continually.

Your truck needs a boatload of ZDDP about as much as my G would need an SAE 10w monograde for the winter.
 
Sorry for reviving an old thread. I also have an 08 F150. I have a few bottles of STP oil additive that has been sitting for a while and I want to get rid of it. I plan on doing an oil change this weekend with Castrol Magnatec 5w30. I see that the general levels of zinc are around 900 ppm. The STP has about 400-500 ppm of zinc. Would adding this to my oil be too much? I just want to use it up already lol
 
It's not additive. It's dilution ratio averaging. 400 + 800 (in equal amounts) comes out 600 ... You won't do much to the ZDDP levels. You will add a bunch of Polyisobutalene (sp?), and that is poor mans VII's, so you are not doing your oil any favors ...

Unless your vehicle has 200,000 miles and is burning oil
grin.gif
 
Zddp matters really only in flat tappet camshaft engines, a study in the 70s found the average American OHV flat tappet V8 of the time saw the least tappet / camshaft wear with a level of about 1200ppm.
 
I personally never had a 'technical' problem with adding vast amounts of ZDDP to oil. Provided your thioacid has been properly neutralised with zinc oxide, ZDDP is not that chemically aggressive, and will simply float around in the oil until it's required to replenish the tribofilms. Think of ZDDP like you eating loads of vitamin tablets. At the end of the day, your body will simply absorb what it needs and no more.

For me the question is why you would ever go to very high ZDDP levels? ZDDP is a brilliant additive and the first 0.1% in oil works absolute wonders! However subsequent increments will give you less and less impact on wear and oxidation. It's a simple case of diminishing returns. You're far better off limiting ZDDP early and adding 'something else' (like Moly) to give you an extra kick in performance, if that's what you're chasing.

From the cat's point of view, under normal operating temperatures, the catalyst will only see Phosphorus (from the ZDDP) if you're burning bulk oil (ie if your losing it through bad valve seals or because you've got a stuck oil ring). If you're losing oil via the PCV system, you are probably burning light base oil but not ZDDP. However if you really whack you're bulk oil temperature (above 150°C) for long periods, expect to see some ZDDP decomposition and a lot more Phos heading down your tailpipe.
 
The standard ILSAC M1 5W30 has 800 ppm Phos and 900 ppm Zinc
The Euro M1 0W40 has 1000 ppm Phos and 1100 ppm Zinc
The diesel truck M1 TDT 5W40 has 1100 ppm Phos and 1300 ppm Zinc
This is all published Mobil 1 data (nominal values) [Here]

Form many years I used Penrite HPR 30 (20W60) without problems, and so did many others in Oz (yes including in an exhaust cat car), it has 1450 ppm Phos and 1570 ppm Zinc.

You probably don't need that much (Penrite is generous with it's ZDDP), but I like the Euro levels of ~1000 ppm, having said that most now use ILSAC levels at about 700-900 ppm without problems. High zinc is mostly for older diesel engines or older flat tappet petrol(gas) engines.
 
For what it's worth, I've always felt that for PCMO, 1000 ppm of Phos is where you want to be. Dropping it to 500 ppm (as some low SAPS oils require) is deffo too low in my opinion regardless of what supplementary anti-wear you might have in the oil. I'd also argue that the level of Phos in the US is too low because whilst the spec allows you to go upto 800 ppm, there are many oils around where it's quite a way away from the maximum level.

Not maximizing the benefits of ZDDP (consistent with cat longevity) is to my mind illogical. ZDDP is cheap and easy to make and arguably the most cost-effective additive in any oil. Not putting in a goodly amount of ZDDP is like going to one of those highly annoying restaurants where they give you a decently sized steak but skimp on the chips!
 
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Originally Posted By: SonofJoe
those highly annoying restaurants where they give you a decently sized steak but skimp on the chips!

I know !! What is it with those expensive fancy-pants steak restaurants, where the veggies and spuds are an expensive optional extra.
 
Originally Posted By: SR5
Originally Posted By: SonofJoe
those highly annoying restaurants where they give you a decently sized steak but skimp on the chips!

I know !! What is it with those expensive fancy-pants steak restaurants, where the veggies and spuds are an expensive optional extra.

And they leave your meat out to rot for a while before you eat it!!
 
Originally Posted By: SonofJoe
I personally never had a 'technical' problem with adding vast amounts of ZDDP to oil. Provided your thioacid has been properly neutralised with zinc oxide, ZDDP is not that chemically aggressive, and will simply float around in the oil until it's required to replenish the tribofilms.

Sometimes I wonder if the contention that (too) high ZDDP (say, up to 1200-1400 ppm P) is competing against other polar additives/base oils for surface contact activation ...... implying inferior and probably detrimental lubricating outcome is an issue that's overblown?
 
Interesting thread.

Sometime ago Forced Performance issued an article on this very point and seem to come to the conclusion that high zinc/phos as a good thing (perhaps not for the cat) but in terms of engine wear and in particular turbocharger wear. I have attached the link below and as you will see the Mobil 1 10w/30 showed excessive wear on the thrust bearing of the turbo. I'm sure that oils have progressed since the article was released back in 2010 but still a good resource nonetheless. As you will see - in turbo'd performance motors their suggestion is a high zinc/phos oil.

http://store.forcedperformance.net/merch...Motor%20Oil.pdf
 
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