The unique TGOJ class M3t from 1930 is based on the Ljungström turbine and was one of the very few truly successful steam turbine locomotive designs worldwide, which made them prime motive power, hauling heavy iron ore trains for almost 25 years. They look a bit odd with their front-mounted turbine machinery with gearbox and their short two-axle tenders, but the design had to be a compromise in order to fit the existing turntables on the TGOJ network.

These turbine locomotives are interesting to watch and listen to when they work hard - not the typical hard puffing sound of traditional steam engines, but rather a loud constant hissing and whining.

Although they became obsolete when the TGOJ mainline was electrified in the 1950s, all three M3t have been preserved and can today be seen at the locomotive museum in Grängesberg.