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SAE J300_201501

SAE J300_201501
SAE J300_201501

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STANDARD J300? JAN2015

Issued 1911-06 Revised 2015-01 Superseding J300? APR2013 Engine Oil Viscosity Classification

RATIONALE

This revision continues the process of extending the SAE Engine Oil Viscosity Classification system to lower high-temperature high-shear-rate (HTHS) viscosities by adding two new high-temperature viscosity grades – SAE 12 and SAE 8 – to SAE J300 with minimum HTHS viscosities of 2.0 and 1.7 mPa·s respectively. The benefit of establishing new viscosity grades is to provide a framework for formulating lower HTHS engine oils in support of the ongoing quest of Original Equipment Manufacturers (OEMs) to improve fuel economy.

The 100°C kinematic viscosity (KV100) ranges of the new viscosity grades overlap to provide adequate formulating space for these grades. How to assign a single high-temperature viscosity grade to an engine oil with KV100 in the overlap regions is covered in Section 6 of this document.

1. SCOPE

This SAE Standard defines the limits for a classification of engine lubricating oils in rheological terms only. Other oil characteristics are not considered or included.

2. REFERENCES

2.1 Applicable Documents

The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the latest issue of SAE publications shall apply.

2.1.1 SAE Publications

Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), https://www.wendangku.net/doc/3411387596.html, .

SAE J1510

Lubricants for Two-Stroke-Cycle Gasoline Engines SAE J1536 Two-Stroke-Cycle Engine Oil Fluidity/Miscibility Classification

2010-01-2286 Covitch, M., Brown, M., May, C., Selby, T. et al., "Extending SAE J300 to Viscosity Grades below SAE 20," SAE Int. J. Fuels Lubr. 3(2):1030-1040, 2010, doi:10.4271/2010-01-2286.

2.1.2 ASTM Publications

Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, https://www.wendangku.net/doc/3411387596.html,

SAE INTERNATIONAL J300? Revised JAN2015 Page 2 of 9 ASTM D97 Standard Test Method for Pour Point of Petroleum Oils

ASTM D445 Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and the Calculation of Dynamic Viscosity)

ASTM D2500 Standard Test Method for Cloud Point of Petroleum Oils

ASTM D3244 Standard Practice for Utilization of Test Data to Determine Conformance with Specifications

ASTM D3829 Standard Test Method for Predicting the Borderline Pumping Temperature of Engine Oil

ASTM D4683 Standard Test Method for Measuring Viscosity at High Temperature and High-Shear Rate by Tapered Bearing Simulator

ASTM D4684 Standard Test Method for Determination of Yield Stress and Apparent Viscosity of Engine Oils at Low Temperature

ASTM D4741 Standard Test Method for Measuring Viscosity at High Temperature and High-Shear Rate by Tapered-Plug Viscometer

ASTM D5133 Standard Test Method for Low Temperature, Low Shear Rate, Viscosity/Temperature Dependence of Lubricating Oils Using a Temperature-Scanning Technique

ASTM D5293 Standard Test Method for Apparent Viscosity of Engine Oils Between –30 and –5 °C Using the Cold-Cranking Simulator

ASTM D5481 Standard Test Method for Measuring Apparent Viscosity at High-Temperature and High-Shear Rate by Multicell Capillary Viscometer

2.1.3 Other Publications

CEC L-36-90 The Measurement of Lubricant Dynamic Viscosity Under Conditions of High Shear

CRC Report No. 409 Evaluation of Laboratory Viscometers for Predicting Cranking Characteristics of Engine Oils at

0 °F and –20 °F, April 1968

2.2 Related Publications

The following publications are provided for information purposes only and are not a required part of this SAE Technical Report.

2.2.1 ASTM Publications

Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, Tel: 610-832-9585, https://www.wendangku.net/doc/3411387596.html,

ASTM Data Series DS 62 The Relationship Between High-Temperature Oil Rheology and Engine Operation -

A Status Report

ASTM STP 1068 High-Temperature, High-Shear Oil Viscosity - Measurement and Relationship to

Engine Operation

ASTM STP 1143 Low-Temperature Lubricant Rheology: Measurement and Relevance to Engine

Operation

ASTM Research Report RR-D02-1442Cold Starting and Pumpability Studies in Modern Engines

ASTM Research Report D02-1767 Interlaboratory Study to Establish Precision Statements for ASTM D4683-10,

D5481-10 and D4741-12

SAE INTERNATIONAL J300? Revised JAN2015 Page 3 of 9 3. SIGNIFICANCE AND USE

The limits specified in Table 1 are intended for use by engine manufacturers in determining the engine oil viscosity grades to be used in their engines, and by oil marketers in formulating, manufacturing, and labeling their products. Oil marketers are expected to distribute only products which are within the relevant specifications in Table 1.

The application of ASTM D3244 is used only for dispute resolution and shall not modify the limiting values in Table 1.

Two series of viscosity grades are defined in Table 1: (a) those containing the letter W and (b) those without the letter W. Single viscosity-grade oils (“single-grades”) with the letter W are defined by maximum low-temperature cranking and pumping viscosities, and a minimum kinematic viscosity at 100 °C. Single-grade oils without the letter W are based on a set of minimum and maximum kinematic viscosities at 100 °C, and a minimum high-shear-rate viscosity at 150 °C. The shear rate will depend on the test method used. Multiviscosity-grade oils (“multigrades”) are defined by both of the following criteria:

a. Maximum low-temperature cranking and pumping viscosities corresponding to one of the W grades, and

b. Maximum and minimum kinematic viscosities at 100 °C and a minimum high-shear-rate viscosity at 150 °C corresponding to one of the non-W grades.

Table 1 - SAE viscosity grades for engine oils (1)(2)

Caution: kinematic viscosity ranges for SAE 8 to SAE 20 viscosity grades partially overlap. How to assign a single viscosity grade to an engine oil satisfying the kinematic viscosity specifications of more than one grade is covered in Section 6 of this document.

SAE Viscosity Grade

Low-Temperature (°C) Cranking Viscosity (3), mPa·s Max Low-Temperature (°C) Pumping Viscosity (4) mPa·s Max with No Yield Stress (4) Low-Shear-Rate Kinematic Viscosity (5) (mm 2/s) at 100 °C Min Low-Shear-Rate Kinematic Viscosity (5) (mm 2/s) at 100 °C Max High-Shear-Rate Viscosity (6) (mPa·s) at 150 °C Min 0W 6200 at –35 60 000 at –40 3.8 — — 5W 6600 at –30 60 000 at –35 3.8 — — 10W 7000 at –25 60 000 at –30 4.1 — — 15W 7000 at –20 60 000 at –25 5.6 — — 20W 9500 at –15 60 000 at –20 5.6 — — 25W 8 12 13 000 at –10 — — 60 000 at –15 — — 9.3 4.0 5.0 — <6.1 <7.1 1.7 2.0 16 — — 6.1 <8.2 2.3 20 — — 6.9 <9.3 2.6 30 — — 9.3 <12.5 2.9 40 — — 12.5 <16.3 3.5 (0W-40, 5W-40, and 10W-40 grades) 40 — — 12.5 <16.3 3.7 (15W-40, 20W-40, 25W-40, 40 grades) 50 — — 16.3 <21.9 3.7 60 — — 21.9 <26.1 3.7

1. Notes—1 mPa·s = 1 cP; 1 mm /s = 1 cSt

2. All values, with the exception of the low-temperature cranking viscosity, are critical specifications as defined by ASTM D3244 (see text, Section7.)

3. ASTM D5293: Cranking viscosity – The non-critical specification protocol in ASTM D3244 shall be applied with a P value of 0.95.

4. ASTM D4684: Note that the presence of any yield stress detectable by this method constitutes a failure regardless of viscosity.

5. ASTM D445

6. ASTM D4683, ASTM D4741, ASTM D5481, or CEC L-36-90. 4. LOW-TEMPERATURE TEST METHODS

The low-temperature cranking viscosity is measured according to the procedure described in ASTM D5293 and is reported in milliPascal·seconds (centipoise). Viscosities measured by this method have been found to correlate with the ability of engines to start at low temperature.

SAE INTERNATIONAL J300? Revised JAN2015 Page 4 of 9 The pumping viscosity is a measure of an oil's ability to flow to the engine oil pump and provide adequate oil pressure during the initial stages of operation. The pumping viscosity is measured in milliPascal·seconds (centipoise) according to the procedure in ASTM D4684. This procedure uses the Mini-Rotary Viscometer to measure either the existence of yield stress or the viscosity in the absence of measured yield stress after the sample has been cooled through a prescribed slow cool (so-called TP1) cycle. This cooling cycle has predicted as failures several SAE 10W-30 and SAE 10W-40 engine oils which are known to have suffered pumping failures in the field after short-term (two days or less) cooling. These field failures are believed to be the result of the oil forming a gel structure that results in excessive yield stress and/or viscosity of the engine oil. The significance of the ASTM D4684 method is projected from the preceding SAE 10W-30 and SAE 10W-40 data.

Limited test work has shown that in a few specific instances, borderline pumping temperature (ASTM D3829), and/or Scanning Brookfield method (ASTM D5133) can provide additional information regarding low-temperature performance. It is suggested that these tests be conducted when formulating new engine oils, or when there are significant changes in base oil or additive components of existing products.

Because engine pumping, cranking, and starting are all important at low temperatures, the selection of an oil for winter operation should consider both the viscosity required for successful oil flow, as well as that for cranking and starting, at the lowest ambient temperature expected.

A manufacturer may not release a product if its low-temperature cranking viscosity as measured by the manufacturer exceeds the maximum limit for its W grade. Similarly, a manufacturer may not release a product if its CCS viscosity as measured by the manufacturer is less than or equal to the stated limit of the next lower W grade. If multiple, operationally-valid CCS measurements are obtained at a given temperature, the average value is to be used to judge suitability for release. Appendix A contains examples of the application of ASTM D3244 in resolving disputes between laboratories as to whether a product conforms to a non-critical cranking viscosity specification.

5. HIGH-TEMPERATURE TEST METHODS

Kinematic viscosity at 100 °C is measured according to ASTM D445, and the results are reported in mm2/s (centistokes). Kinematic viscosities have been related to certain forms of oil consumption and have been traditionally used as a guide in selecting oil viscosity for use under normal engine operating temperatures. Also, kinematic viscosities are widely used in specifying oils for applications other than in automotive engines.

High-temperature high-shear-rate (HTHS) viscosity measured at 150 °C and reported in mPa·s (centipoise) is widely accepted as a rheological parameter which is relevant to high-temperature engine performance. In particular, it is generally believed to be indicative of the effective oil viscosity in high-shear components of an internal combustion engine (for example, within the journal bearings and between the rings and cylinder walls) under severe operating conditions. While the specific temperature and shear rate conditions experienced by an oil in a particular application depend on mechanical design and operating parameters, the measurement conditions specified in Table 1 are representative of a wide range of engine operating conditions.

Many commercial engine oils contain polymeric additives for a variety of purposes, one of the most important of which is viscosity modification. Specifically, the use of such additives in creating multigrade oils is commonplace. However, oils containing a significant polymeric additive concentration, whether for viscosity modification or another lubricant function, are generally characterized by having a non-Newtonian, “shear thinning” viscosity (i.e., a viscosity which decreases with increasing shear rate).

To insure that polymer-containing oils do not create a situation in which the viscosity of the oil decreases to less than a specified limit, minimum values of HTHS viscosity are assigned to each of the non-W viscosity grades in Table 1. A special situation exists regarding the SAE 40 grade. Historically, SAE 0W-40, 5W-40, and 10W-40 oils have been used primarily in light-duty engines. These multigrade SAE 40 oils must meet a minimum HTHS viscosity limit of 3.5 mPa·s.

In contrast, SAE 15W-40, 20W-40, 25W-40, and 40 oils have typically been used in heavy-duty engines. The manufacturers of such engines have required HTHS viscosity limits consistent with good engine durability in high-load, severe service applications. Thus, SAE 15W-40, 20W-40, 25W-40, and single-grade 40 oils must meet a minimum HTHS viscosity limit of 3.7 mPa·s.

There are three acceptable methods for the measurement of HTHS viscosity. For rotational viscometer methods ASTM D4683 and CEC L-36-90 (ASTM D4741), the shear rate is 1.0 x 106 s–1. For the capillary viscometer method, ASTM

SAE INTERNATIONAL J300? Revised JAN2015 Page 5 of 9 D5481, the shear rate is 1.4 x 106 s–1 at the wall. The latter shear rate has been found to provide HTHS viscosities in the capillary viscometer that are equivalent to those obtained by the rotational viscometer methods.

6. LABELING

In properly describing the viscosity grade of an engine oil according to this document, the letters “SAE” must precede the grade number designation. In addition, for multigrade oil formulations this document requires that the W grade precede the non-W grade, and that the two grades be separated by a hyphen (i.e., SAE 10W-30). Other forms of punctuation or separation are not acceptable.

Engine oils not meeting the technical requirements of any viscosity grade in this document shall not bear any SAE viscosity grade on the label.

It is possible for an engine oil to meet the kinematic viscosity requirements of more than one high temperature viscosity grade (SAE 8 through SAE 20). In labeling a single-grade or multigrade oil meeting the kinematic viscosity requirements of more than one grade, only the highest viscosity grade satisfied by the HTHS viscosity shall be referred to on the label. Examples for proper labeling are provided in Table 2.

Table 2 – Labeling examples

Kinematic Viscosity High-Shear-Rate-Viscosity

(mm2/s) at 100°C (mPa·s) at 150°C SAE Viscosity Grade

7.0 2.6 20

7.0 2.4 16

7.0 2.1 12

5.6 2.1 12

5.6 1.9 8

Most oils will meet the viscosity requirements of at least one of the W grades. Nevertheless, consistent with historic practice, any Newtonian oil may be labeled as a single-grade oil (either with or without a W). Oils which are formulated with polymeric viscosity index improvers for the purpose of making them multiviscosity-grade products are non-Newtonian and must be labeled with the appropriate multiviscosity grade (both W and high-temperature grade). Since each W grade is defined on the basis of maximum cranking and pumping viscosities as well as minimum kinematic viscosities at 100 °C, it is possible for an oil to satisfy the requirements of more than one W grade. In labeling either a W grade or a multiviscosity grade oil, only the lowest W grade satisfied may be referred to on the label. Thus, an oil meeting the requirements for SAE grades 10W, 15W, 20W, 25W, and 30 must be referred to as an SAE 10W-30 grade only.

An oil must meet the pumping requirements of the lowest W grade satisfied by the cranking viscosity. If the W grade defined by the pumping viscosity is higher than the lowest grade satisfied by the cranking viscosity, the oil does not meet the requirements of this document.

The low temperature limits in Table 1 are those derived by the ASTM Low Temperature Engine Performance task force from engine studies conducted in the 1990’s [ASTM STP 1143]. Individual equipment manufacturers may use these limits as guidelines to recommend the appropriate winter grade of engine oil, or may apply more limiting criteria (cranking viscosity, pumping viscosity or other) to oils that they recommend for use in their engines.

If the kinematic viscosity at 100 °C does not meet the requirements of the lowest W grade satisfied by the cranking viscosity, then the oil does not meet the requirements of this document.

Some engine oils are prediluted, usually to assist in mixing with fuel when used in certain two-stroke-cycle engines. If any viscosity grade in SAE J300 is used to describe a prediluted engine oil, the grade indicated should relate to the viscosity of the oil in its undiluted state. In displaying SAE J300 viscosity grades of prediluted oils, containers should indicate that the SAE grade applies to the oil in its undiluted state.

More accurately, the rheological properties of two-stroke-cycle engine oils should be identified using the terminology and grades described in SAE J1536. Further information on prediluted oils is also provided in SAE J1510.

7. NOTES

7.1 Marginal Indicia

A change bar (I) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only.

PREPARED BY THE SAE FUELS AND LUBRICANTS TC 1 - ENGINE LUBRICATION

APPENDIX A

The following examples show the use of ASTM D3244 in resolving disputes between laboratories as to whether a product conforms to a non-critical cranking viscosity specification. Each example starts with a summary statement, with the details of the case shown in the numbered sections.

CAUTION: For the purpose of illustration, the reproducibility used in the examples below is that shown in ASTM D5293 for the automated CCS device with a methanol bath (7.3%). The user of this version of SAE J300 is cautioned

to refer to the most current version of ASTM D5293 to determine the appropriate reproducibility of the specific

low-temperature cranking viscosity method to use in any dispute.

Example 1 -- When CCS result indicates a higher grade, with Assigned Test Value inside Acceptance Limit

A user measures CCS of an SAE 5W-X oil and claims it to be an SAE 10W-X grade. The Assigned Test Value is within the Acceptance Limit. Resolution: There is insufficient evidence to conclude that the oil should have been labeled as an SAE 10W-X.

1. A manufacturer measures the CCS viscosity per ASTM D5293-04 of oil A as 6550 mPa·s @ –30 °C.

2. The manufacturer releases the product, oil A, as an SAE 5W-X oil, since the test result is less than 6600 mPa·s

maximum.

3. A user measures the CCS viscosity of oil A (that is branded as SAE 5W-X) at –30 °C and obtains a result of

6750 mPa·s. CCS Reproducibility is 7.3% in this example.

4. Then per ASTM D3244-07 paragraph 7.3.5 (Eq. 2):

a. The Acceptance Limit, AL, (based on an average of 2 results) is equal to: 6600 mPa·s + {0.255 x (6600 x 0.073)

x 1.645} = 6802, where 0.255 and 1.645 are values from ASTM D3244-07 Figure 1.

b. The absolute difference between the manufacturer's result and the user's result = |6550 - 6750| = 200.

c. Reproducibility of the test method in this example at 6600 mPa·s is: 6600 x 0.073 = 482.

d. Since the difference of 200 is less than 482, both results can be used to calculate the Assigned Test Value, ATV.

ATV = (6550 + 6750)/2 = 6650.

e. Since the ATV (6650) is less than the AL (6802), there is insufficient evidence to conclude that oil A should have

been labeled as an SAE 10W-X.

Example 2 - CCS result exceeds grade maximum limit

A manufacturer measures the CCS above the maximum limit for the targeted grade. Resolution: CCS can be measured again one or more times and the average taken. If the average remains above the maximum limit, the oil can not be released in the target grade.

1. A manufacturer measures the CCS viscosity per ASTM D5293-04 of oil B as 6650 mPa·s @ –30 °C.

2. The product, oil B, cannot be released as an SAE 5W-X oil without further investigation or rework, since it exceeds the

6600 limit. The manufacturer has the option of re-measuring CCS viscosity @ –30 °C as many times as it chooses to determine if the average value is less than the 6600 limit.

Example 3 - When CCS result indicates a higher grade, with Assigned Test Value outside Acceptance Limit

A user measures the CCS of an SAE 5W-X oil and finds it to be an SAE 10W-X grade. The Assigned Test Value is outside the Acceptance Limit for SAE 5W-X. Resolution: The parties need to conduct further analysis to determine whether the oil meets SAE 5W-X limits.

1. A manufacturer measures the CCS viscosity per ASTM D5293-04 of oil C as 6590 mPa·s @ –30 °C.

2. The manufacturer releases the product, Oil C, as an SAE 5W-X oil.

3. A user measures the CCS viscosity of Oil C (that is branded as SAE 5W-X) at –30 °C and obtains a result of

7050 mPa·s; ASTM D5293 reproducibility is 7.3% in this example.

4. Then per ASTM D3244-07 paragraph 7.3.5 (Eq. 2):

a. The Acceptance Limit is the same as example 1, 6802 mPa·s.

b. The absolute difference between the manufacturer's result and the user's result = | 6590 - 7050 | = 460.

c. Reproducibility of the test method in this example at 6600 mPa·s is: 6600 x 0.073 = 482.

d. Since the difference of 460 is less than 482, both results can be used to calculate the Assigned Test Value, ATV.

ATV = (6590 + 7050)/2 = 6820.

e. Since the ATV (6820) exceeds the AL (6802), further investigation by the parties involved is necessary to resolve

the discrepancy.

Example 4 - When CCS result indicates a higher grade but cannot calculate Assigned Test Value

A user measures the CCS of an SAE 5W-X oil and claims it to be an SAE 10W-X grade. The Assigned Test Value (ATV) can not be calculated. Resolution: The parties need to determine why the CCS results exceed the test reproducibility.

1. A manufacturer measures the CCS viscosity per ASTM D5293-04 of oil C as 6450 mPa·s @ –30 °C.

2. The manufacturer releases the product oil C as an SAE 5W-X oil.

3. A user measures the CCS viscosity of oil C (that is branded as SAE 5W-X) at –30 °C and obtains a result of

7150 mPa·s; ASTM D5293 reproducibility is 7.3% in this example.

4. Then per D3244-07 paragraph 7.3.5 (Eq. 2):

a. The Acceptance Limit is the same as example 1, 6802 mPa·s.

b. The absolute difference between the manufacturer's result and the user's result = | 6450 - 7150 | = 660.

c. Reproducibility of the test method in this example at 6600 mPa·s is: 6600 x 0.073 = 482.

d. Since the difference of 660 is larger than 482, the results can not be used to calculate the Assigned Test Value,

ATV.

e. Further investigation by the parties involved is necessary to resolve why the measured values exceed the

Reproducibility stated in ASTM D5293-04.

Example 5 - When CCS result indicates a lower grade than labeled, with Assigned Test Value inside Acceptance Limit

A user measures the CCS of an SAE 5W-X oil and claims it to be an SAE 0W-X. The Assigned Test Value is within the Acceptance Limit for SAE 5W-X. Resolution: There is insufficient evidence to conclude that the oil should have been labeled as an SAE 0W-X.

1. A manufacturer measures the CCS viscosity per ASTM D5293-04 of oil D as 6250 mPa·s @ –35 °C.

2. The manufacturer releases the product, oil D, as an SAE 5W-X oil.

3. A user measures the CCS viscosity of oil D (that is branded as an SAE 5W-X) at –35 °C and obtains a result of

6000 mPa·s. CCS reproducibility is 7.3% in this example.

4. Then per ASTM D3244-07 paragraph 7.3.5 (Eq. 2):

a. The Acceptance Limit, AL, for a 0W (–35 °C test temperature) is equal to: 6200 mPa·s + {0.255 x (6200 x 0.073)

x (-1.645)} = 6010, where 0.255 and -1.645 are values from ASTM D3244-07 Figure 1.

b. The absolute difference between the manufacturer's result and the user's result = | 6250 - 6000 | = 250.

c. Reproducibility of the test method in this example at is: 6200 x 0.073 = 453.

d. Since the difference of 250 is less than 453, both results can be used to calculate the Assigned Test Value, ATV.

ATV = (6250 + 6000)/2 = 6125.

e. Since the ATV (6125) exceeds the AL (6010), there is insufficient evidence to conclude that this product, oil D,

should have been labeled as SAE 0W-X rather than SAE 5W-X.

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