In 1975, for the 1976 model year, the tub and frame were modified from earlier versions. The frame went from a partially open channel/boxed frame with riveted crossmembers, to majoritively boxed with welded crossmembers, and from parallel rails to widening fore to aft to benefit stability. and the body tub became more rounded. The windshield frame and windshield angle were also changed, meaning that tops from 1955 to 1975 will not fit a 1976-1983 CJ-5 and vice versa. The rear axle was also changed in 1976 from a Dana 44 to an AMC-manufactured model 20 that had a larger-diameter ring gear, but used a two-piece axleshaft/hub assembly instead of the one-piece design used in the Dana.