AJAX (1964 engine company)

Ajax Ltd. (commonly known as AJAX) is an American manufacturer of diesel engines for trucks, based in of McCook, Illinois. AJAX, originally announced in 1959, is a 30-70 joint venture between and operated by Gorganstien Trucks and Murdovsky Motors. Diesel engine production started in May 1969. Later on during development, AJAX contributed to the Gorganstien Micro Deltic, which was essentially Gorganstien's version of D. Napier & Son's Napier Deltic engine; however, in the 1990s, their on-highway versions of the Deltic engine, which was part of the Micro Deltic series, were discontinued, despite most service parts remaining in production until the 2010s.

The AJAX plant was built on a land grant site adjacent to a Murdovsky plant that made the troublesome 1.8 L Diesel I6 which was developed as a successor of the 1.5 L Murdovsky 4D85E I6. Production of that engine began in 1991.