Compliance – Properly Displaying Viscosity Grade

Viscosity is one of the most important properties of motor oil and generally the first piece of information a consumer looks for, beyond brand, when making a buying decision. For this reason, the viscosity grade is shown on the front label in plainly visible print. Further, many brands display it on the front label in a font size and prominence that is second only to the brand name. Due to its importance, uniform standards, laws and regulations are in place that require motor oil labels to display the viscosity grade of the product, and specify how it must be displayed.

One example is seen in Section IV. Uniform Regulations B. Uniform Regulation for the Method of Sale of Commodities in the NIST Handbook 130 (HB-130). This regulation states; “The label on any vehicle engine (motor) oil container, receptacle, dispenser, or storage tank, and any invoice or receipt from service on an engine that includes the installation of vehicle engine (motor) oil dispensed from a receptacle, dispenser, or storage tank, shall contain the viscosity grade classification preceded by the letters “SAE” in accordance with SAE International’s latest version of SAE J300, Engine Oil Viscosity Classification.” 

And to be in accordance with SAE J300, it is required that a “W” precedes the non-W grade on the label and the two grades are delineated by a hyphen. By way of example, whereas SAE 5W-30 is displayed in accordance with SAE J300; 5W-30, SAE 5W30, and 5W*30 are not.  

The only exception to the above cited HB-130 regulation states that; “if an invoice or receipt from service on an engine has limited room for identifying the viscosity, brand, and service category, then abbreviated versions of each may be used on the invoice or receipt and the letters “SAE” may be omitted from the viscosity classification.” This exception, however, does not apply to labels on motor oil bottles.

Another example of regulations pertaining to how the viscosity must appear on motor oil labels is seen in Chapter 14, Article 9 – Labeling [13480] (b), in California’s Business and Professional Code. The regulation states; “When the product is a lubricant, as defined by Section 13400, each sign or label shall also have in letters or numerals, plainly visible, the viscosity grade classification as determined in accordance with the SAE International latest standard for engine oil viscosity classification SAE J300 or manual transmission and axle lubricants viscosity classification SAE J306, as applicable, and shall be preceded by the letters ‘SAE’.”

Whereas the regulations are clear, PQIA continues to see motor oils on store shelves where the viscosity grade is not preceded by SAE. As seen in the most recent group of samples PQIA reported on, for example, the “5W-30” displayed on the front label on the Mobil Super is not preceded by “SAE.” Although the results of the tests conducted on this sample show the product meets the SAE J300 specification for an SAE 5W-30 and SAE does precede the viscosity grade shown on the back label, the viscosity grade on the front label, the one consumers see first, does not display “SAE.” 

So why is displaying “SAE” important, and for that matter, why is a hyphen required to be shown between the two grades for multigrades? Whereas some might think of it as nit picking, consider that PQIA has examined a number of brands where such omissions confuse and mislead consumers.

One of the most glaring examples of this was seen on the labels of the “Mileage 365” brand motor oils PQIA examined in 2018. The front label on one product prominently displays “10-40.” This could be interpreted by a reasonable consumer to mean the motor oil is an SAE 10W-40 viscosity grade, but our tests show it is not. The back label of the product states “10-40 means a motor oil with a viscosity ranging from 4.4 cSt to 14 cSt @ 100° Celsius.” Such a viscosity range is not consistent with any multigrade motor oil as defined by SAE J300.  The Mileage 365 “10-30” and “5-30” bottles examined by PQIA were likewise labeled. 

A similar example is seen with the “Q” brand motor oil examined by PQIA in 2018. Whereas the front label on this product displays “5*30” in large print (which could be interpreted by a consumer as meaning it’s an SAE 5W-30 viscosity grade), the label also states in smaller print “Viscosity Range 5 To 30.” Adding to the confusion, the back label states “10-30 means the viscosity range from 10 to 30.” 

So why is it important to comply with the regulations concerning viscosity-grade labeling? First of all, it is required by law in most states. Furthermore, it’s a slippery slope if by way of exceptions and precedent it becomes acceptable to omit the “SAE” from the viscosity grade declaration on motor oil labels. Because if this is acceptable, by way of extension, will it also be acceptable to omit the hyphen in multigrades, or drop the “W?” 

By not following uniform standards and regulations, as PQIA has seen, some marketers define the viscosity grade declaration on the labels to whatever they intend it to mean, a practice that could potentially mislead or deceive consumers into buying the wrong grade of motor oil for their vehicle and possibly violating their warranty and/or cause harm to their engine.   

Learn More

NIST Handbook 130 2020 (see page 137,

California Legislative Information – ARTICLE 9. Labeling [13480 – 13490] 

PQIA – Read the Labels on Motor OIl Before you Buy


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