Since this era, the focus of domestic demand gradually started shifting from bulldozers to hydraulic shovels. Additional considerations, such as ease of operation, also became an important aspect of design.
In order to improve productivity at construction sites, it is crucial to reduce the number of loadings to large Dump trucks. Although more and more sites were switching to Dump trucks as large as a 32-ton class, everybody was behind with development of loaders. D155S was developed to be the world's largest dozer shovel to fill the gap. A total of 234 units were produced until its discontinuation in 1989.
Since its first emergence in 1951, it took only 50 years for the hydraulic shovel to establish its primary position on construction sites worldwide. Its size ranges from mini to super size depending on the scale of construction, and during the half century, it kept evolving by achieving a minimum rear-swing radius and adapting styles that would work with characteristics of each site. Mirroring the movement of a human hand, a hydraulic shovel will continue to evolve during the 21st century.