TOKYO — Osamu Masuko, the long-serving, soft-spoken chairman of Mitsubishi Motors Corp. who hammered out his company's partnership with Nissan Motor Co., leaves behind a stronger carmaker but one that is still a work in progress after several fitful revival attempts.
Masuko died of heart failure Aug. 27, three weeks after stepping down over health concerns. He was 71. At the time of his retirement, when he took a "special adviser" role, Masuko was one of Japan's oldest and longest-serving automotive chiefs. He led Mitsubishi for 15 years.
Masuko became president of Mitsubishi Motors in 2005 and cycled through various positions at the top, including the CEO and chairman posts, during a pivotal period at the small Japanese player. Masuko hatched numerous plans to reboot the brand's flagging fortunes, oversaw its foray into electrified vehicles and helped pen its 2016 partnership with Nissan.
With Mitsubishi then part of the Renault-N…