Don't candy-coat it, 427, tell us what you REALLY think..
Question - Zinc amounts
- Thread starter Francis
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I mean,
Lotta peeps add a little SLOB to the oil in their push-rod V6s and 8s, 427.. In my roller-skaer Hyundai with the twin-cam 4-banger, since the "poisoned catalyst talk started some months back, I add only an oil filter to my OCI, but there's a lotta folks with older cars and SM oil...
Could THAT many peeps be wrong?
Lotta peeps add a little SLOB to the oil in their push-rod V6s and 8s, 427.. In my roller-skaer Hyundai with the twin-cam 4-banger, since the "poisoned catalyst talk started some months back, I add only an oil filter to my OCI, but there's a lotta folks with older cars and SM oil...
Could THAT many peeps be wrong?
Maybe I am missing something, but I don't read much disagreement in this thread. I think that 427Z06 rightly pointed out that my explaination may be simplified - it was. I hope that we all agree that the nature of cat poisoning by contaminants can vary depending on the contaminants, environment, ect. I was trying to point out that many factors other than just phosphate can contribute to cat poisoning. I don't think that 427Z06 suggested otherwise (please feel free to correct me if I am wrong, always).
As for SLOB or any other additive, anyone that uses such products are concluding that they can improve upon the oil that they have chosen to use. I think that such people are often wrong in that conclusion. However, since nearly everything can be improved, a few may accomplish the goal - by design or by luck.
As for SLOB or any other additive, anyone that uses such products are concluding that they can improve upon the oil that they have chosen to use. I think that such people are often wrong in that conclusion. However, since nearly everything can be improved, a few may accomplish the goal - by design or by luck.
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Hey, whatever they have to do to get that "OOOO what a feeling" "Zoom-zoom-zoom" " their BOLD MOVE" "to feel LIKE A ROCK" ...
..they could always stand in line to spend $600+ for a plastic box
..they could always stand in line to spend $600+ for a plastic box
No harm adding SLOB for us folks who don't give a rip about the catalytic converter. (Whether it would harm a cat I don't really know.) SLOB is useful to extend the OCI. Probably the best use of SLOB would be to add a few ounces every 1000 miles to make up for zddp depletion.
Only in some engines that are equipped with flat tappets would the additional ZDDP be useful. (Recall the Sequence IIIG is run on a flat tappet pushrod pig iron V6.) Why pay for the additional cost of SLOB and hope you don't screw up the chemistry of the oil when you could buy oil that is already properly formulated with additional ZDDP, and/or other additives like borate esters.
Has the full compliment of SM (or similar) tests ever been independently run on an oil and then on that same oil with SLOB added to compare the results? How do you know it's actually doing anything good?
I don't say it's doing any good, only that there are probably thousands of posts here and undoubtedly elsewhere extolling the advantages of various and sundry additives.. VSOT, SLOB, Lucas, heck, even a couple of our sponsors sell the stuff to put in the gas, the oil, the transmission.. This 106HP DOHC with the (so I'm told) rollerized cams surely doesn't need it. VSOT thickened the oil so much I never used it again after the time or two I did use it, on my old car. Didn't hurt anything, but it went 250K without that stuff, so between that and the news that the adds foul the cat, I don't use it. When SLOB came out (or I became aware of it, I should say) I used it a time or two on this car, didn't noticed a difference, quit using it. But if someone uses it to stretch an OCI, or they don't care if the cat fouls, whaddya gonna do? If there's harm, I fail to see it if they're footing the bill for new cats.
Makes em feel better, maybe. Junior chemists, as was said..
Pardon me for joining the thread, but I've been looking for some info on the whole flat tappet vs. depleted ZDDP thing. I have an MG, which I'm running Castrol 10w30 in. If I'm understanding the various thread about this correctly, if it's already well broken in, it should be okay as long as I'm not trying to do long oil changes. Does that sound right? It sees less than 1000 miles a year, and I usually change it once a year. I keep an eye on the valve lash to make sure it's not growing significantly, but should I add anything else? Different oil?
Dave, what year is your MG? If it's an older one you may want some additive. Specialty Formulations (one of our site experts) makes an additive, SX-UP, specifically formulated for older cars from the muscle car era.
Another option is to run heavy duty engine oil (dual rated gas and diesel). If you live by a Murrays, they sell Motorcraft Diesel 10w30 in quarts for $2.39. That would give you the extra antiwear additives in a well formulated oil.
Another option is to run heavy duty engine oil (dual rated gas and diesel). If you live by a Murrays, they sell Motorcraft Diesel 10w30 in quarts for $2.39. That would give you the extra antiwear additives in a well formulated oil.
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Paul, it's a 1977 Midget with the Triumph 1500 engine, the same one the Spitfire used. Thanks for the tip on the diesel oil though, I hadn't considered that option.
Yeah, any dual rated Diesel oil (so long as it has SL along with the CF-4 or whever letter it's at now). I only see 15w40 diesel oil except for that Motorcraft at Murrays. May want to stock up. Motorcraft is supposed to be very good oil too.
Some of the SL rated PCMO have the same amount of ZDDP as my SL/CF-4 rated HDEO that I use now in my Jeeps' engines so what's the difference?If an engine builder says to use an SL rated oil at the time of it's conception, and wasn't concerned then with my cats dying then,why should I use a SM rated oil now?
And why do you think that the car makers were not concerned about cat poisoning back then. Why do you think the reducing ZDDP has been an issue if the car makers were not complaining?
As I understand it the typical SL PCEO is around 1000 ppm zinc and similar phos. HDEO SL should be higher, say 1200 or better ppm. Some High Mileage oils may be higher too. Someone once posted that SL Citgo Ultralife was 1200 ppm.
Fear of cat poisoning became a bigger issue as EPA required automakers to warranty the cat for more miles. Nothing strikes fear into auto companies hearts more than added costs, especially warranty costs.
Fear of cat poisoning became a bigger issue as EPA required automakers to warranty the cat for more miles. Nothing strikes fear into auto companies hearts more than added costs, especially warranty costs.
Because the emmsion requirements are changing.
http://theoildrop.server101.com/forums/s...8327#Post748327
Nowadys with smaller engines and tighter emmisions ZDDP ,or any type of cat creating problems,are of greater concern.To be honest has anyone really heard of an all-out cat dying issue in great numbers?Almost every vehicle I know of,of great age, is blowing oil and what-not with the original cat still on board.Didn't that article say that driving at highway speed/high-load, to burn off the residue ZDDP,along with calcium and other additives makes the cat live longer anywho?
If you keep the OCI to 1000 miles or less. I don't believe you'll have any issues with your Castrol 10w30. As mentioned before, the Sequence IIIG test is run on a flat-tappet pushrod pig-iron V6 under much more severe conditions than any street vehicle will ever likely see. If you want the added assurance of using an HDEO 10w30, it won't hurt, and CAT poisoning is probably the least of your concerns.
And you're correct, the break in procedures with flat-tappet cams is most critical.
Thanks!
Decent read indead.
The reason I personally feel somewhat uneasy about SM oils in my cars is that even though the P limit is 800ppm, we see just 600ppm in most gas SM oils.
The API test is obsolete and does not look at the wear of timing chains (in OHV) and variable timing wheels. Until API uses newer test engine design, I would rather use ACEA certified oils (tougher wear standards) or use enough SLOB to bring P to 800ppm or so.
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