isuzu motors ltd. (japanese: いすゞ自動車株式会社, hepburn: isuzu jidōsha kabushiki-kaisha, tyo: 7202), trading as isuzu (japanese pronunciation:[isɯzɯ], /iˈsuːzuː/), is a japanese commercial vehicle and diesel engine manufacturing company headquartered in tokyo. its principal activity is the production, marketing and sale of isuzu commercial vehicles and diesel engines.