In April, 1988, a motorsports team was established at the Passenger Car Technology Center in Okazaki City (Aichi Prefecture) in Japan. Their sole purpose was to enhance their efforts toward the Dakar Rally. The team mainly took charge of advanced development and SBM, which was commissioned by Sonauto, was to continue its participation in the production of the rally cars. The team immediately began to improve the prototype in 1989, and at the same time started developing the “Okazaki Proto”, an original research vehicle proposed by the Japanese squad as a base for the next model. For the 1989 model, improvements in reliability and performance, including countermeasures for overheating problems were implemented, specifically, enlargement and change in the layout of the radiators, use of aluminum for differential carriers and housings, and adoption of a 5-speed transmission manufactured by Hewland Engineering, were carried out. Incidentally, a new rule reduced the air restrictor of the turbocharger to 45mm or less. This was incorporated in the engine, but the power output was increased by improving the compressor. The MITSUBISHI MOTORS team entered Cowan, Lartigue, De Silva, Shinozuka, Tambay and Fontenay in the 1989 model PAJERO/MONTERO Prototypes.

The 11th Dakar Rally chose a course that would bypass Algeria for the first time due to political instability, opting for Tunisia's capital of Tunis. The organizers laid out a new route south of Libya to reach the east side of the Ténéré Desert. In addition, the cross-country raid was complying with the rules issued by the International Automobile Federation, and Group T regulations were introduced. The non-modified production car class became "T1", the modified production car class became "T2", and the prototype class became "T3". Actually, it was based on the rules of the usual Dakar Rally, and there were no major changes. However, the production of at least 1000 units over 12 consecutive months of the standard car they were based on was required for the homologation of T1 and T2 cars.

The 11th edition's total distance amounted to 10,794 km, including 6,281 km of competitive stages (SS). Although the scale of the event had not changed significantly from the previous year, the start of the event was brought forward by one week with the start at Versailles and the journey to southern France beginning on December 25. The event had scheduled a rest day in Agadez in Niger on January 3rd and was due to finish at Lac Rose outside Dakar on the 13th. That year, the MITSUBISHI MOTORS team fought a hard battle with the Peugeot factory teams, but the MITSUBISHI MOTORS team was unable to overcome the top-running Peugeots because of frequent engine issues caused by the effects of unrefined locally provided gasoline. The only fastest SS time set by a PAJERO/MONTERO was that of Shinozuka in the Bamako-Labé special stage in Mali and Guinea. Nonetheless, Tambay took a well-deserved third overall, Tijsterman was fifth overall, Shinozuka sixth, Fontenay seventh and Da Silva tenth, with the PAJERO/MONTEROS occupying five out of the top 10 positions, a testimony to its high reliability. On top of that, the Marreau siblings of France, who were participating in a PAJERO/MONTERO with the 3.0L 6G72 type V6 gasoline engine, won in the modified production car class.