An indoor laboratory procedure is proposed for the evaluation and diagnosis of the tire contributions to the annoying, erratic motions of the vehicle induced when travelling over longitudinally grooved pavement. Instrumented measurements of vehicular motions on these grooved highways are used to set direction for the laboratory procedures.A particular test configuration of the vehicle on an indoor chassis dynamometer is described. Test data, obtained with this configuration, show the periodic recurrence of mechanical interactions of the tire and simulated road grooves corresponding to the spatial repetition of the grooves. These data also exhibit correlation with subjective assessments of vehicular performance on the grooved highways. Quantitative agreement between the vibratory measurements on the highways and the laboratory measurements obtained by the described methods provides substantive support.A method of diagnosing the regional tread and road groove interactions is also proposed. Experienced technicians can readily identify favorable tire alterations with the diagnostic procedures, enabling isolation and suppression of excessive interactions.