5.1 This test method measures a lubricant's ability to protect hypoid final drive axles from abrasive wear, adhesive wear, plastic deformation, and surface fatigue when subjected to low-speed, high-torque conditions. Lack of protection can lead to premature gear or bearing failure, or both.

5.2 This test method is used, or referred to, in specifications and classifications of rear-axle gear lubricants such as:

5.2.1 Specification D7450.

5.2.2 American Petroleum Institute (API) Publication 1560.

5.2.3 SAE J308.

5.2.4 SAE J2360.

1.1 This test method, commonly referred to as the L-37-1 test, describes a test procedure for evaluating the load-carrying capacity, wear performance, and extreme pressure properties of a gear lubricant in a hypoid axle under conditions of low-speed, high-torque operation.3

1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.2.1 Exceptions—Where there is no direct SI equivalent such as National Pipe threads/diameters, tubing size, or where there is a sole source supply equipment specification.

1.2.1.1 The drawing in Annex A6 is in inch-pound units.

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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific warning statements are provided in 7.2 and 10.1.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.