Curious as to what the big difference is between the two ratings. I know SN is newer than SM. I happen to have both Synpower and Peak Synthetic if both versions (I actually bought the Peak SM & SN at the same time on clearance a while back. Was not aware they had different ratings) and I'm curious as to know whether they actually changed the formulas when they got the more recent SN rating.
SM & SN What's the difference?
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SN is newer version of SM, they are standards that an oil must adhere to regardless of how the actual oil is formulated.
SN improves two big ways on SM , one is fuel efficiency ( see below ) and seal compatibility and durability.
Heres note from API site :
" Introduced in October 2010 for 2011 and older vehicles, designed to provide improved high temperature deposit protection for pistons, more stringent sludge control, and seal compatibility.
API SN with ResourceConserving matches ILSAC GF-5 by combining API SN performance with improved fuel economy, turbocharger protection, emission control system compatibility, and protection of engines operating on ethanol-containing
fuels up to E85."
http://www.pqiamerica.com/apiserviceclass.htm
SN improves two big ways on SM , one is fuel efficiency ( see below ) and seal compatibility and durability.
Heres note from API site :
" Introduced in October 2010 for 2011 and older vehicles, designed to provide improved high temperature deposit protection for pistons, more stringent sludge control, and seal compatibility.
API SN with ResourceConserving matches ILSAC GF-5 by combining API SN performance with improved fuel economy, turbocharger protection, emission control system compatibility, and protection of engines operating on ethanol-containing
fuels up to E85."
http://www.pqiamerica.com/apiserviceclass.htm
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Interesting chart. Very informative. What I'm wanting to know is whether the SM rated Synpower and Peak Synthetic would have passed the SN rating or did they have to tweak the formulas to have them pass the rating. I like to think that they would have passed anyways since they usually state their oils (most name brands) "exceeds API requirements."
Originally Posted By: termigator
Interesting chart. Very informative. What I'm wanting to know is whether the SM rated Synpower and Peak Synthetic would have passed the SN rating or did they have to tweak the formulas to have them pass the rating. I like to think that they would have passed anyways since they usually state their oils (most name brands) "exceeds API requirements."
All synthetics that are by major brands exceed API ratings.
Somtimes they cant move up because they have some additive that is part of their marketing scheme .
For example , Valvoline has " VR1 RACING OIL " it can never be SN or SM because the zinc inside only passes SL. Zinc is GREAT for engine protection , horrible for catalytic converters. Therefore ; the oil quality will pass SM ( or even SN ) but it cannot get approval because it has too much zinc to pass the SN/SM specs.
Interesting chart. Very informative. What I'm wanting to know is whether the SM rated Synpower and Peak Synthetic would have passed the SN rating or did they have to tweak the formulas to have them pass the rating. I like to think that they would have passed anyways since they usually state their oils (most name brands) "exceeds API requirements."
All synthetics that are by major brands exceed API ratings.
Somtimes they cant move up because they have some additive that is part of their marketing scheme .
For example , Valvoline has " VR1 RACING OIL " it can never be SN or SM because the zinc inside only passes SL. Zinc is GREAT for engine protection , horrible for catalytic converters. Therefore ; the oil quality will pass SM ( or even SN ) but it cannot get approval because it has too much zinc to pass the SN/SM specs.
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Originally Posted By: Voltmaster
All synthetics that are by major brands exceed API ratings.
Somtimes they cant move up because they have some additive that is part of their marketing scheme .
( or even SN ) but it cannot get approval because it has too much zinc to pass the SN/SM specs.
Correct. Some misinformed people out there intensely criticized Royal Purple for not meeting some rating spec, but they failed to realize it was because Royal Purple was even BETTER since it had a more stout additive package.
All synthetics that are by major brands exceed API ratings.
Somtimes they cant move up because they have some additive that is part of their marketing scheme .
( or even SN ) but it cannot get approval because it has too much zinc to pass the SN/SM specs.
Correct. Some misinformed people out there intensely criticized Royal Purple for not meeting some rating spec, but they failed to realize it was because Royal Purple was even BETTER since it had a more stout additive package.
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Originally Posted By: Voltmaster
Originally Posted By: termigator
Interesting chart. Very informative. What I'm wanting to know is whether the SM rated Synpower and Peak Synthetic would have passed the SN rating or did they have to tweak the formulas to have them pass the rating. I like to think that they would have passed anyways since they usually state their oils (most name brands) "exceeds API requirements."
All synthetics that are by major brands exceed API ratings.
Somtimes they cant move up because they have some additive that is part of their marketing scheme .
For example , Valvoline has " VR1 RACING OIL " it can never be SN or SM because the zinc inside only passes SL. Zinc is GREAT for engine protection , horrible for catalytic converters. Therefore ; the oil quality will pass SM ( or even SN ) but it cannot get approval because it has too much zinc to pass the SN/SM specs.
Remember, this is grade-dependant as well, which is why the 40-weight oils can have much higher levels of zinc/phos and still be SN or SM.
Originally Posted By: termigator
Interesting chart. Very informative. What I'm wanting to know is whether the SM rated Synpower and Peak Synthetic would have passed the SN rating or did they have to tweak the formulas to have them pass the rating. I like to think that they would have passed anyways since they usually state their oils (most name brands) "exceeds API requirements."
All synthetics that are by major brands exceed API ratings.
Somtimes they cant move up because they have some additive that is part of their marketing scheme .
For example , Valvoline has " VR1 RACING OIL " it can never be SN or SM because the zinc inside only passes SL. Zinc is GREAT for engine protection , horrible for catalytic converters. Therefore ; the oil quality will pass SM ( or even SN ) but it cannot get approval because it has too much zinc to pass the SN/SM specs.
Remember, this is grade-dependant as well, which is why the 40-weight oils can have much higher levels of zinc/phos and still be SN or SM.
The Synpower I have is 5w30, but the Peak Synthetic is 5w20.
Originally Posted By: gfh77665
but they failed to realize it was because Royal Purple was even BETTER since it had a more stout additive package.
You mean, 'even WORSE since it's bad for catalytic converters'.
but they failed to realize it was because Royal Purple was even BETTER since it had a more stout additive package.
You mean, 'even WORSE since it's bad for catalytic converters'.
So if one were to superimpose an SL rated oil in the chart above, would it have better wear protection than SN/SM but less emission systems durability?
Why buy oil with older classification when the current SN/GF-5 rating improves on previous ones overall especially with the US gasoline E85 fuel content?
Why buy oil with older classification when the current SN/GF-5 rating improves on previous ones overall especially with the US gasoline E85 fuel content?
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They think they can get better wear protection from oils with the older SL rating because of the higher zinc content and are willing to sacrifice the improvements on other aspects of the oil to get it. I think QS is trying to corner that market with Defy.
Originally Posted By: martinq
Originally Posted By: gfh77665
but they failed to realize it was because Royal Purple was even BETTER since it had a more stout additive package.
You mean, 'even WORSE since it's bad for catalytic converters'.
And how many cats were ruined by RP? If you make a reckless statement like that, back it up.
I knew some RP hater would crawl out of a hole...
Originally Posted By: gfh77665
but they failed to realize it was because Royal Purple was even BETTER since it had a more stout additive package.
You mean, 'even WORSE since it's bad for catalytic converters'.
And how many cats were ruined by RP? If you make a reckless statement like that, back it up.
I knew some RP hater would crawl out of a hole...
Originally Posted By: gfh77665
because Royal Purple was even BETTER since it had a more stout additive package.
Not about hate, just about facts and is exactly what I'm saying. If you're going to make a reckless statement like that you really should back it up.
If the RP can't meet the SN spec it's for a reason. One reason oils don't meet SN is due to cat-con damage.
because Royal Purple was even BETTER since it had a more stout additive package.
Not about hate, just about facts and is exactly what I'm saying. If you're going to make a reckless statement like that you really should back it up.
If the RP can't meet the SN spec it's for a reason. One reason oils don't meet SN is due to cat-con damage.
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Originally Posted By: martinq
Originally Posted By: gfh77665
because Royal Purple was even BETTER since it had a more stout additive package.
Not about hate, just about facts and is exactly what I'm saying. If you're going to make a reckless statement like that you really should back it up.
If the RP can't meet the SN spec it's for a reason. One reason oils don't meet SN is due to cat-con damage.
I did back it up. Reread. I said: it was BETTER since it had a more stout additive package.
So how many cats were damaged? Still waiting.
Originally Posted By: gfh77665
because Royal Purple was even BETTER since it had a more stout additive package.
Not about hate, just about facts and is exactly what I'm saying. If you're going to make a reckless statement like that you really should back it up.
If the RP can't meet the SN spec it's for a reason. One reason oils don't meet SN is due to cat-con damage.
I did back it up. Reread. I said: it was BETTER since it had a more stout additive package.
So how many cats were damaged? Still waiting.
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Originally Posted By: gfh77665
Originally Posted By: martinq
Originally Posted By: gfh77665
because Royal Purple was even BETTER since it had a more stout additive package.
Not about hate, just about facts and is exactly what I'm saying. If you're going to make a reckless statement like that you really should back it up.
If the RP can't meet the SN spec it's for a reason. One reason oils don't meet SN is due to cat-con damage.
I did back it up. Reread. I said: it was BETTER since it had a more stout additive package.
So how many cats were damaged? Still waiting.
Loading an oil full of ZDDP doesn't necessarily make it "better".
Originally Posted By: martinq
Originally Posted By: gfh77665
because Royal Purple was even BETTER since it had a more stout additive package.
Not about hate, just about facts and is exactly what I'm saying. If you're going to make a reckless statement like that you really should back it up.
If the RP can't meet the SN spec it's for a reason. One reason oils don't meet SN is due to cat-con damage.
I did back it up. Reread. I said: it was BETTER since it had a more stout additive package.
So how many cats were damaged? Still waiting.
Loading an oil full of ZDDP doesn't necessarily make it "better".
Originally Posted By: gfh77665
I did back it up. Reread. I said: it was BETTER since it had a more stout additive package.
More is not better. We have formulas using 1/4 of the moly that older formulas have and they out perform them. So, less is better? What about the new nano formulas coming out that have 1/2 the friction and maybe 15% of the wear of old 'stout' formulas?
I did back it up. Reread. I said: it was BETTER since it had a more stout additive package.
More is not better. We have formulas using 1/4 of the moly that older formulas have and they out perform them. So, less is better? What about the new nano formulas coming out that have 1/2 the friction and maybe 15% of the wear of old 'stout' formulas?
Originally Posted By: martinq
If the RP can't meet the SN spec it's for a reason. One reason oils don't meet SN is due to cat-con damage.
As Overkill points out, it's really not that simple. A boatload of ZDDP doesn't make an oil great, and certainly isn't ideal for every application. On the other hand, using SJ or earlier levels of ZDDP in an SN vehicle isn't going to cause your catalytic converter to explode. Cats predated SM/GF-4 and SN/GF-5 by a substantial margin, and we didn't see them failing left and right. I don't think harsh oil burners are easy on cats, regardless of how low the phosphorus content is.
The oil companies and automakers have to walk some fine lines. Engine durability and emissions system durability are both important for warranty. If a quart per 1000 miles of oil consumption is acceptable to most North American automakers, I'm sure they don't want an engine and a cat grenading at the same time. Of course, the oil companies don't want to pull out all the stops in blending, ingredients, and R&D and have to soak us $20 per quart, either.
For the record, RP does have SN/GF-5 oils now. Even when they were still SL/GF-3, the oils did not have ridiculously high amounts of ZDDP in them, either. Their SL oils basically "stumbled across" the limits, rather than pole vaulted over them. Their Synerlec additive, however, was a bit of a different story, and wasn't in the RP 0w-40 before either, due to the ACEA specifications it claimed.
If the RP can't meet the SN spec it's for a reason. One reason oils don't meet SN is due to cat-con damage.
As Overkill points out, it's really not that simple. A boatload of ZDDP doesn't make an oil great, and certainly isn't ideal for every application. On the other hand, using SJ or earlier levels of ZDDP in an SN vehicle isn't going to cause your catalytic converter to explode. Cats predated SM/GF-4 and SN/GF-5 by a substantial margin, and we didn't see them failing left and right. I don't think harsh oil burners are easy on cats, regardless of how low the phosphorus content is.
The oil companies and automakers have to walk some fine lines. Engine durability and emissions system durability are both important for warranty. If a quart per 1000 miles of oil consumption is acceptable to most North American automakers, I'm sure they don't want an engine and a cat grenading at the same time. Of course, the oil companies don't want to pull out all the stops in blending, ingredients, and R&D and have to soak us $20 per quart, either.
For the record, RP does have SN/GF-5 oils now. Even when they were still SL/GF-3, the oils did not have ridiculously high amounts of ZDDP in them, either. Their SL oils basically "stumbled across" the limits, rather than pole vaulted over them. Their Synerlec additive, however, was a bit of a different story, and wasn't in the RP 0w-40 before either, due to the ACEA specifications it claimed.
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