This SAE Recommended Practice establishes the test procedure, environment, and instrumentation for determining the maximum exterior sound level for passenger cars, multipurpose vehicles, and light trucks with a gross vehicle weight rating (GVWR) of 4540 kg (10 000 lb) or less.
This Recommended Practice is intended for use when the maximum sound generating capability of any applicable vehicle is to be measured. The test procedure is characterized by having fixed terminal conditions (attainment of rated engine speed at a fixed end point on the test site) in contrast to the procedure of SAE Standard J986b, Sound Level For Passenger Cars And Light Trucks, which has fixed initial conditions (specified initial vehicle speed at a fixed acceleration point on the test site). Full-throttle acceleration and closed-throttle deceleration of the vehicle are included in both procedures.
Sound levels determined in accordance with this Recommended Practice are essentially independent of transmission and axle ratios for a vehicle family having otherwise identical characteristics. Thus, this Recommended Practice is particularly applicable to development testing of vehicle families or to test development where vehicle performance differences are to be minimized.