Confirmation Tests for SAE J57 Test Procedure Revision

A description of the confirmation tests conducted by the Tire Noise Standards Committee for the revised J57, Truck Tire Noise Measurement Standard is presented. The goal of these tests was to determine the repeatability and variability associated with the procedures and ranges of parameters specified in this revision. Two sets of tires were tested over a range of measurement parameters. The parameters examined included tire type, ambient temperature, pavement surface temperature, coast-by speed, and trailer drawbar length. Finally, the total coast-by noise measurement variability according to this new procedure is estimated.