JTEKT Torsen North America carries a Rochester, New York, lineage that began with Vernon Gleasman’s differential design and The Gleason Works’ gear-making expertise. Since 1984, the JTEKT subsidiary has made Torsen helical-gear differentials for automakers, with a presence in original-equipment programs and the North American aftermarket. Its history includes an early contract for the AM General HMMWV and later adoption in Audi Quattro vehicles.