This is the final report of a study of the way in which tire/road noise changes as the pavement ages and wears. Measurements of the levels of noise generated at the tire/road-surface interface were made on sections of a variety of asphaltic and concrete compositions ranging in age from newly laid to 29 years. Data from these measurements are presented in graphical form showing levels and trends of levels with time. While the measurements made in this study do not portray the noise levels at the roadside, they do rank order the source noise levels of the various surfaces devoid of the noise absorption characteristics of the surface. An interpretation of the data is provided to assist highway planners, designers, or environmental engineers. As an add-on to the main study, a comparison of the noise from studded tires and non-studded tires of the same tread design was made for a variety of roadway surface types.