SAE J300 vs SAE Viscosity Grade Charts

ZeeOSix

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I'm wondering why the various SAE Viscosity Grade charts I can find don't correspond with the SAE J300 minimum KV100 (cSt) for SAE 20 grade oil.

The other Viscosity Grade minimums specified for KV100 are pretty close for 30, 40 and 50 grades ... so that might just be due to "sloppy" chart makers (?). But SAE 20 grade seems to be off compared to SAE J300 in every chart I can find. See the examples below. Any reason why?

Is it because of this flag note in the SAE Viscosity Grade chart? If so, isn't the SAE J300 minimum KV100 specs based on something similar?

1648605831782.png


Note that the 2015 version of SAE J300 shown below is the most current version.

J300 Minimum KV100 for SAE Grades
SAE 20 - 6.9 cSt
SAE 30 - 9.3 cSt
SAE 40 - 12.5 cSt
SAE 50 - 16.3 cSt

SAE J300 (2015 Version).jpg



In both SAE Viscosity Grade Charts below, the blue lines show the minimum KV100 value called out in SAE J300.
The red lines show the values that correspond to the minimum KV100 in the viscosity grading graph.
The SAE 20 in both charts show the minimum KV100 to be quite a bit lower than the J300 specification.
The lower end of SAE 20 in both of these charts is in the 5.7-5.8 cSt range when SAE J300 calls out 6.9 cSt. Why ??

Engine and Gear Oil SAE Viscosity Grades Chart - Copy.jpg



The KV100 in SAE J300 and in this SAE Viscosity Chart are basically the same at 9.3 cSt, but again for SAE 20 they are way off.

SAE Viscosity Chart.jpg
 
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ZeeOSix

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The answer is your table posted is after the J300 update in 2015. The last 2 you posted were prior to the update. Most of them posted are still old. SAE 8,12, and 16 were added in 15.

David
Thanks ... Do you happen to have a copy or link to an updated SAE Viscosity Grade chart that corresponds to J300, 2015 version?

Do the older (pre-2015) versions of SAE J300 show the minimum KV100 defined for SAE 20 to be around 5.8 cSt?
 
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As I recall the old minimum was 5.8 cSt but I don't recall seeing it anywhere near that low in practice. Likely due to the 2.6 HTHS requirement.
 
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That is what we use every day. We have extended the upper and lower range which covers our Pro Stock and Alcohol cars in drag racing that extended beyond the J300 spec. Since there are no standards to address those it is the Wild West on what people make and what they call them. I am speaking of racing oils specifically. We decided to Simply publish a logical progression and adhere to it.

David
 

ZeeOSix

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That is what we use every day. We have extended the upper and lower range which covers our Pro Stock and Alcohol cars in drag racing that extended beyond the J300 spec. Since there are no standards to address those it is the Wild West on what people make and what they call them. I am speaking of racing oils specifically. We decided to Simply publish a logical progression and adhere to it.

David
Thanks for that info. So it seems it basically comes down to all the bar graphs all over the internet not being updated to reflect the latest SAE J300 viscosity grade specs (ie, the low end of "20 grade" is lower than J300). Guess people got tired of updating their bar graphs all the time, lol. 🤷‍♂️
 
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