ASTM D6923-08 - 15.10.2008
 
Significance and Use

This is an accelerated engine oil test, performed in a standardized, calibrated, stationary single-cylinder diesel engine that gives a measure of (1) piston and ring groove deposit forming tendency, (2) piston, ring, and liner scuffing and (3) oil consumption. The test is used in the establishment of diesel engine oil specification requirements as cited in Specification D 4485 for appropriate API Performance Category C oils (API 1509). The test method can also be used in diesel engine oil development.

 
1. Scope

1.1 This test method covers stressing an engine oil under modern high-speed diesel operating conditions and measures the oil's deposit control, lubrication ability, and resistance to oil consumption. It is performed in a laboratory using a standardized high-speed, single-cylinder diesel engine.

1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use. Being an engine test method, this test method does have definite hazards that require safe practices (see Appendix X2 on Safety).

1.4 The following is the Table of Contents:

Scope

1

Referenced Documents

2

Terminology

3

Summary of Test Method

4

Significance and Use

5

Apparatus and Installation

6

Intake Air System

6.2.1

Exhaust System

6.2.2

Fuel System

6.2.3

Oil Consumption System

6.2.4

Engine Oil System

6.2.5

Engine Coolant System

6.2.6

Engine Instrumentation

6.2.7

Reagents and Materials

7

Oil Samples

8

Preparation of Apparatus

9

General Engine Assembly Practices

9.1

Complete Engine Inspection

9.2

Copper Component

9.3

Engine Lubricant System Flush

9.4

Engine Piston Cooling Jet

9.5

Engine Measurements and Inspections

9.6

Cylinder Head

9.7

Valve Guide Bushings

9.8

Fuel Injector

9.9

Piston and Rings

9.10

Cylinder Liner

9.11

Compression Ratio

9.12

Engine Timing

9.13

Engine Coolant System Cleaning Procedure

9.14

Calibration and Standardization

10

Test Cell Instrumentation

10.1

Instrumentation Standards

10.2

Coolant Flow

10.3

Fuel Injectors

10.4

Air Flow

10.5

Intake Air Barrel

10.6

Fuel Filter

10.7

Oil Scale Flow Rates

10.8

Test Stand Calibration

10.9

Re-calibration Requirements

10.9.1

Extending Test Stand Calibration Period

10.9.2

Test Run Numbering

10.10

Humidity Calibration Requirements

10.11

Calibration of Piston Deposit Raters

10.12

Procedure

11

Engine Break-in Procedure

11.1

Cool-down Procedure

11.2

Warm-up Procedure

11.3

Shutdowns and Lost Time

11.4

Periodic Measurements

11.5

Engine Control Systems

11.6

Engine Coolant

11.6.1

Engine Fuel System

11.6.2

Engine Oil Temperature

11.6.3

Exhaust Pressure

11.6.4

Intake Air

11.6.5

Post-Test Procedures

11.7

Piston Ring Side Clearances

11.7.1

Piston Ratings

11.7.2

Ring Gap End Increase

11.7.3

Cylinder Liner Wear

11.7.4

Cylinder Liner Bore Polish

11.7.5

Photographs

11.7.6

Calculation and Interpretation of Results

12

Test Validity

12.1

Calculations

12.4

Quality Index

12.4.1

Oil Consumption

12.4.2

Report

13

Forms and Data Dictionary

13.1

Test Validity

13.2

Report Specifics

13.3

Precision and Bias

14

Precision

14.1

Bias

14.2

Keywords

15

Annexes

Engine and Parts Warranty

Annex A1

Instrument Locations, Measurements and Calculations

Annex A2

Cooling System Arrangement

Annex A3

Intake Air Mass Flow Sensor Installation

Annex A4

Fuel System Design and Required Components

Annex A5

Oil System

Annex A6

Additional Report Forms

Annex A7

Engine Assembly and Inspection Information

Annex A8

Flushing Instructions and Apparatus

Annex A9

Warm-up, Cool-down and Testing Conditions

Annex A10

Piston and Liner Rating Modifications

Annex A11

Return Goods Authorization Claim Form

Annex A12

Appendixes

Various Examples of Supplemental Information for Reference Purposes

Appendix X1

Safety

Appendix X2

 
2. Referenced Documents

D235-22

Standard Specification for Mineral Spirits (Petroleum Spirits) (Hydrocarbon Dry Cleaning Solvent)

D445-26

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

D5967-21

Standard Test Method for Evaluation of Diesel Engine Oils in T-8 Diesel Engine

D5966-22

Standard Test Method for Evaluation of Engine Oils for Roller Follower Wear in Light-Duty Diesel Engine

D524-15(2025)e1

Standard Test Method for Ramsbottom Carbon Residue of Petroleum Products (Includes all amendments and changes 8/11/2025).

D5844-98

Standard Test Method for Evaluation of Automotive Engine Oils for Inhibition of Rusting (Sequence IID) (Withdrawn 2003)

D5862-09

Standard Test Method for Evaluation of Engine Oils in Two-Stroke Cycle Turbo-Supercharged 6V92TA Diesel Engine (Withdrawn 2009)

D5302-01a

Test Method for Evaluation of Automotive Engine Oils for Inhibition of Deposit Formation and Wear in a Spark-Ignition Internal Combustion Engine Fueled with Gasoline and Operated Under Low-Temperature, Light-Duty Conditions (Withdrawn 2003)

D5185-26

Standard Test Method for Multielement Determination of Used and Unused Lubricating Oils and Base Oils by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES)

D4863-13

Standard Test Method for Determination of Lubricity of Two-Stroke-Cycle Gasoline Engine Lubricants (Withdrawn 2022)

D6202-02

Standard Test Method for Automotive Engine Oils on the Fuel Economy of Passenger Cars and Light-Duty Trucks in the Sequence VIA Spark Ignition Engine (Withdrawn 2009)

D6594-26

Standard Test Method for Evaluation of Corrosiveness of Diesel Engine Oil at 135 °C

D6681-23

Standard Test Method for Evaluation of Engine Oils in a High Speed, Single-Cylinder Diesel Engine—Caterpillar 1P Test Procedure

E29-22

Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

E344-26a

Terminology Relating to Thermometry and Hydrometry (Includes all amendments and changes 4/21/2026).

G40-25a

Standard Terminology Relating to Wear and Erosion (Includes all amendments and changes 12/8/2025).

ASTM Deposit Rating Manual 20

(formerly CRC Manual 20) For Stock #TMCMNL20, visit the ASTM website, www.astm.org, or contact ASTM International Customer Service at service@astm.org.

SAE J183

Engine Oil Performance and Engine Service Classification Available from Society of Automotive Engineers (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001.

D4052-22

Standard Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density Meter

D3524-14(2020)

Standard Test Method for Diesel Fuel Diluent in Used Diesel Engine Oils by Gas Chromatography

D4175-24e2

Standard Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants (Includes all amendments and changes 6/9/2026).

D4485-24

Standard Specification for Performance of Active API Service Category Engine Oils

D4739-26

Standard Test Method for Base Number Determination by Potentiometric Hydrochloric Acid Titration

D3338-08

Standard Test Method for Estimation of Net Heat of Combustion of Aviation Fuels

D664-24

Standard Test Method for Acid Number of Petroleum Products by Potentiometric Titration

D976-21e1

Standard Test Method for Calculated Cetane Index of Distillate Fuels (Includes all amendments and changes 2/23/2023).

D1298-24

Standard Test Method for Density, Relative Density, or API Gravity of Crude Petroleum and Liquid Petroleum Products by Hydrometer Method

D1319-25

Standard Test Method for Hydrocarbon Types in Liquid Petroleum Products by Fluorescent Indicator Adsorption

D613-26

Standard Test Method for Cetane Number of Diesel Fuel Oil

D2500-23

Standard Test Method for Cloud Point of Petroleum Products and Liquid Fuels

D2622-26

Standard Test Method for Sulfur in Petroleum Products by Wavelength Dispersive X-ray Fluorescence Spectrometry

D2709-22

Standard Test Method for Water and Sediment in Middle Distillate Fuels by Centrifuge

D86-23ae2

Standard Test Method for Distillation of Petroleum Products and Liquid Fuels at Atmospheric Pressure (Includes all amendments and changes 11/4/2024).

D93-26

Standard Test Methods for Flash Point by Pensky-Martens Closed Cup Tester

D97-17b(2022)

Standard Test Method for Pour Point of Petroleum Products (Includes all amendments and changes 11/29/2022).

D130-26

Standard Test Method for Corrosiveness to Copper from Petroleum Products by Copper Strip Test