SAE J1940 oil is designed for use in small spark and compression ignition engines, including outdoor equipment such as mowers, construction and utility vehicles, and off-highway recreational vehicles, according to the Society of Automotive Engineers. These engines have a maximum 1.0 liter sweep volume displacement.
J1940 is a horsepower rating determined by the SAE. This rating does not cover engines in on-road vehicles, motorcycles or boats. The current standard requires all engines produced after October 1, 2013 to perform within 95 percent of the power and torque labeled by the manufacturer. The manufacturer also has to disclose the engine's revolutions per minute. The SAE standards, which are reviewed and revised every five years by the SAE, are intended to ensure engines provide consumers with the advertised level of power and torque.
In engines rated J1940, lawn equipment manufacturer Briggs & Stratton recommends using SAE 30 oil for all-purpose use above 40 degrees, and 10W-30 for cold-weather starting and wider temperature variations up to 100 degrees. Synthetic 5W-30 should be used for extreme temperatures from -20 to 120 degrees, and 5W-30 for winter use and generally cold conditions. The company also recommends using high-quality detergent oil labeled "For Service SF, SG, SH, SJ" or higher and avoiding special additives.