Thanks for the links. I'll have to take some time to examine them.
ZDDP Levels Limit OCI??
- Thread starter Ron AKA
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I've had a chance to compare these, and you are correct it is not possible to do a perfect apples to apples comparison. However, if one sticks to what looks like the less trivial items, the reality is that there is not a lot of difference between SL and SM. Following is what I saw:
Phosphorous max has been lowered to 0.8 from 1.0%. There is now a minimum of 0.6%. If you don't claim qualification to GF-4, then there is still a minimum of 0.6%, but no maximum. This is interesting in that now a non GF-4 SM can potentially contain all kinds of ZDDP, and certainly more than SJ or SL.
Total Deposits have been reduced from 45 mg to 35 mg. Not claiming GF-4 allows you to say SM and still have 45 mg.
Sulfur is a new requirement with a maximum of 0.5% for 0w and 5w. If you forego GF-4 then there is no limit. 10w is limited to 0.7%.
Viscosity Increase - Although the test appears to have changed it appears more restrictive. Now seems to be 150% with SM in 100 hours compared to 275% in 80 hours with SL.
Cam Wear - Significant reduction in wear allowed from 120 to 90. I feel better!!
Fuel Efficiency - As everyone is aware, more is required in SM compared to SL.
Actually the change from SJ to SL seems more significant than from SL to SM. Although the phosphorous reduction was likely the big one for everyone to swallow.
The Amsoil 0w-30/5w-30/10w-30 and the Mobil 1/EP, 5w-30/10w-30 all have API/SM levels of zinc and phosphorus.
I know of no oils that consistently last longer in service, so I think this is a non-issue. However note that these formulations are using other additives to suppliment the reduction in ZnDTP, such as borate esters and other types of anti-oxidants.
TS
I know of no oils that consistently last longer in service, so I think this is a non-issue. However note that these formulations are using other additives to suppliment the reduction in ZnDTP, such as borate esters and other types of anti-oxidants.
TS
One thing is for sure, when you compare the SM and SL specifications, it makes you wonder why people are so fearfull of SM oil.
Oh yea! SM has less ZDDP so it must be worse! (sarcasm off)
Oh yea! SM has less ZDDP so it must be worse! (sarcasm off)
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I'm sure that the world doesn't revolve around zddp. ZDDP is probably a cheaper way to get there. I'm sure more expensive alternatives are employed and will be employed to a further extent in the future.
What is the most frustrating aspect of it is that it's ALWAYS the cheap and highly functional (appear the most vital) agents that ALWAYS encounter conflicts with other technologies (catalytic converters, etc.).
What is the most frustrating aspect of it is that it's ALWAYS the cheap and highly functional (appear the most vital) agents that ALWAYS encounter conflicts with other technologies (catalytic converters, etc.).
And that's a good thing. Could you imagine the confusion if the world started revoloving on ZDDP and all of a sudden we had 20 hour days?
For these tests, I'd feel a lot more confortable knowing that they require a more relevant engine than a pushrod GM V6 ..........
Which ZDDP?
http://corporate.lubrizol.com/PressRoom/MediaCoverage/pdflibrary/LNG_ZDDP.pdf
SL test
http://www.swri.org/4org/d08/GasTests/IIIFtest/default.htm
SM test
http://www.swri.org/4org/d08/GasTests/IIIGtest/default.htm
Harder test but can allow 3x more cam wear for a pass?
http://corporate.lubrizol.com/PressRoom/MediaCoverage/pdflibrary/LNG_ZDDP.pdf
SL test
http://www.swri.org/4org/d08/GasTests/IIIFtest/default.htm
SM test
http://www.swri.org/4org/d08/GasTests/IIIGtest/default.htm
Harder test but can allow 3x more cam wear for a pass?
The ZDDP levels were only lowered after several SAE papers showed that levels over 0.3 did not diminish wear any further after being run in API test engines. These are under the most severe conditions that do not normally exist in even "severe" driving within the population.
In less severe conditions even lower levels would do well.
If you compare virgin oil verses UOA levels you will see that the depletion is minimal or even zero.
More relevant is that the SM standards far exceed wear protection of SL oils.
I welcome the new SM standard.
aehaas
In less severe conditions even lower levels would do well.
If you compare virgin oil verses UOA levels you will see that the depletion is minimal or even zero.
More relevant is that the SM standards far exceed wear protection of SL oils.
I welcome the new SM standard.
aehaas
It is also important to understand how new standards get published. The oil companies actually develop better oils first. They submit results to API. Then the SAE and API vote several times until everybody agrees to the new standards. Finally the new standard is accepted and released. This is an over generalization but it tells the story. The new oil exists before the standard is released.
aehaas
aehaas
The valvetrains are different, and the test is run for 100 hours (SM) instead of 80 hours (SL). The SM IIIG test is definitively more severe.
Read up on the development of the IIIG test if you don't believe me.
Using a flat tappet pushrod 3.8L engine designed decades ago presents a much more difficult test than say a modern belt driven rollarized valvetrain engine. In short, it's a good thing. But if it provides you with any comfort, a couple of other engine designs are used in the SM/GF-4 sequence of tests.
is using ZDDP additive (whether it be STP or SLOB) in an SM rated oil a "waste"
only thinking about this for my Galant...i think the cat has had it by now anyway
only thinking about this for my Galant...i think the cat has had it by now anyway
A chart showing the effect of using this companies Borate Esters in combination with ZDDP vs. ZDDP alone. SURPRISE! Less wear than ZDDP alone. But... But... But... Yes, Virginia, there are additives in SM oil that work better than ZDDP in SL oil.
Thanks for the good info, Winston.
Thanks Winston....so how about the ZDDP additive thrown in to a motor with SM oil???
Hey, I dont claim to be an expert on all of this stuff. Just posting some data that I found.
However, as far as the idea of adding extra ZDDP to an SM oil, why do you think that would help? More does not necessarily equal better.
I have been thinking about this whole SL SM info some more. Clearly there is a way to reduce wear and reduce catalyst contaminating ZDDP in oil. API most likely knew this when they wrote the SM spec. They wrote the spec to force oil mfg's to use the newer, better additives. Makes sense, no? In the end we all benefit.
However, as far as the idea of adding extra ZDDP to an SM oil, why do you think that would help? More does not necessarily equal better.
I have been thinking about this whole SL SM info some more. Clearly there is a way to reduce wear and reduce catalyst contaminating ZDDP in oil. API most likely knew this when they wrote the SM spec. They wrote the spec to force oil mfg's to use the newer, better additives. Makes sense, no? In the end we all benefit.
what if i was running an SL?
using the on sale oils in the old girl.
using the on sale oils in the old girl.
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