The Class 58 was one of British Rail’s boldest diesel experiments — a locomotive built with power, simplicity, and heavy freight firmly in mind. Introduced in the early 1980s, the Class 58 broke away from traditional British locomotive design. Instead of a single rigid frame, it used a modular construction, borrowing ideas from American freight practice. This made the locomotives quicker to build and easier to maintain — at least in theory. Powered by a Ruston-Paxman RK3 engine delivering 3,300