What weight oil over and over

Are you aware of drivetrain failures, recalls, etc? Obviously, the cliche "the engineers knew what they were doing" is not exactly true.
Yep, the engineers who designed my Takata air-bags knew exactly what they were doing.

Have a look at this critical recall list

"The critical and alpha labels are for airbags specified by the vehicle manufacturer as posing a significantly higher risk of injury or death......It's recommended that owners of vehicles with critical or alpha airbags should stop driving their vehicles immediately until the airbag has been replaced."
 
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If the specified oil viscosity was actually from the people who designed & tested the motor you would have a very solid point. any amount of testing, research, or speculation I can do as a mechanic pales in comparison to what the manufacturer does in developing a new engine.

But for quite a while now the specifications we receive as consumers are not based solely on the needs of the engine but instead a compromise between engineers, accountants, attorneys & politicians. and this is why you see widely varying viscosity specified for the exact same engine based on the laws of the country it is being delivered to.

There is a current Mazda engine made in Japan and shipped worldwide, identical motors with no changes for various markets, In the USA 0w-20 Only. & Europe & Mexico 0w-20 or 5w-30, elsewhere a wide range of viscosity up to 10w-50 are specified based on ambient temperature.

Obviously this motor will run on 0w-20, but It would be inaccurate to say that that 0w-20 is ideal for all conditions from Barrow AK to Key west FL, and as long as you live outside the reach of certain laws Mazda will tell you the same.

The Skyactiv in Mexico has 5w-30 but SM rated oil. For the rest of North America including Puerto Rico and Canada it is 0w-20 SN rated. The quality SM rating for Mexico is a step down. Mazda ships their cars world wide with 0w-20
 
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The Skyactiv in Mexico has 5w-30 but SM rated oil. For the rest of North America including Puerto Rico and Canada it is 0w-20 SN rated. The quality SM rating for Mexico is a step down. Mazda ships their cars world wide with 0w-20


Can anyone still find SM or SN oil? Those ratings have been superseded for quite some time now.
 
The Skyactiv in Mexico has 5w-30 but SM rated oil. For the rest of North America including Puerto Rico and Canada it is 0w-20 SN rated. The quality SM rating for Mexico is a step down. Mazda ships their cars world wide with 0w-20
actually, sm is a superior standard because it allows for higher levels of zddp. with sn they reduced the maximum level of zddp as it can cause catalytic converter degradation. that's actually why so many oil bottles clearly say "meets or exceeds" api sn... if it has an adequate amount of zddp for a flat tappet engine, it surely exceeds the sn spec.
 
Can anyone still find SM or SN oil? Those ratings have been superseded for quite some time now.
Just an interesting thing that some people miss when reading the North American Mazda OM. A outdated API standard for Mexico.
 
Can anyone still find SM or SN oil? Those ratings have been superseded for quite some time now.
I could've sworn I picked up a jug of Edge 5W-30 at Walmart the other day that had a different style label, not made in USA, and was SM rated. I didn't pay much attention to it, but maybe it was the "Euro" version?
 
I could've sworn I picked up a jug of Edge 5W-30 at Walmart the other day that had a different style label, not made in USA, and was SM rated. I didn't pay much attention to it, but maybe it was the "Euro" version?
Better look at that label again maybe you got the Mexican version ;)
 
bro I just make every car I own chug conventional or synthetic 15w40.

Except the Honda odyssey 2006 and 2013 camry, camry has 5w30 16 dollar for 3 jug chevron and honda has 5w20 because it was cheap and it works for my purpose, it is babied.
 
Better look at that label again maybe you got the Mexican version ;)
It's actually API SL:D🇲🇽
Edge.jpg
 
1. This site is geared towards obsessive behavior.
2. Are you aware of drivetrain failures, recalls, etc? Obviously, the cliche "the engineers knew what they were doing" is not exactly true.
Drivetrain issues due to design or material issues, yes. Not oil related failures 😎
 
Yep, the engineers who designed my Takata air-bags knew exactly what they were doing.

Have a look at this critical recall list

"The critical and alpha labels are for airbags specified by the vehicle manufacturer as posing a significantly higher risk of injury or death......It's recommended that owners of vehicles with critical or alpha airbags should stop driving their vehicles immediately until the airbag has been replaced."
And how’s this related to oil/lubrication/drivetrain design?
 
actually, sm is a superior standard because it allows for higher levels of zddp. with sn they reduced the maximum level of zddp as it can cause catalytic converter degradation. that's actually why so many oil bottles clearly say "meets or exceeds" api sn... if it has an adequate amount of zddp for a flat tappet engine, it surely exceeds the sn spec.
I believe most recent the Phos (ZDDP) restrictions started with SM, not SN.
If you want a high ZDDP oil in an ILSAC grade (xW20, yW30), then you need a SL.

Having said that, just because its SL, doesn't mean it has to be high ZDDP, only that it can. Also this restriction only applies to ILSAC grades, not to xW40 or above.

That is why Castrol Edge 5W30 A3/B4 with 1000 ppm Zn is API SL. While Castrol Edge 0W40 also with 1000 ppm Zn is API SN.
 
I believe most recent the Phos (ZDDP) restrictions started with SM, not SN.
it appears you are correct about that, this article discusses the matter pretty thoroughly.

Having said that, just because its SL, doesn't mean it has to be high ZDDP, only that it can. Also this restriction only applies to ILSAC grades, not to xW40 or above.
i actually thought it had to do with whether the bottle bears the api "for gasoline engines" starburst symbol... perhaps that is also tied to whether the oil meets a specific ilsac grade, though.

regardless, there are definitely oils that say "meets or exceeds" on the bottle, and list api sn, but they contain more zddp than the api spec allows. mobil 1 15w50 is one example.
 
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it appears you are correct about that, this article discusses the matter pretty thoroughly.

however, there are definitely oils that say "meets or exceeds" on the bottle, and list api sn, but they contain more zddp than the api spec allows. mobil 1 15w50 is one example.
The limits of 800 ppm Phos under SN apply to ILSAC viscosity grades only, xW20 and yW30.

Thicker grades like xW40 and yW50 are allowed higher Phos levels.

The article clearly states "I must point out that these phosphorus level mandates are on SAE 10W-30 and lower viscosity grades only."
 
regardless, there are definitely oils that say "meets or exceeds" on the bottle, and list api sn, but they contain more zddp than the api spec allows. mobil 1 15w50 is one example.
Meets or exceeds is correct language for an API license. Can be used in an improper way but it is what it is. You can verify via the API ELOCS Directory.
 
The limits of 800 ppm Phos under SN apply to ILSAC viscosity grades only, xW20 and yW30.
am i correct in saying that only ilsac oils bear the api "for gasoline engines" starburst? i edited my prior post to clarify that i'd thought that was the determining factor.
 
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