In the Soviet Union, Belarus was responsible for the development of heavy multi-axle military equipment. The unusual projects of Minsk designers include the gigantic 140-ton 12-wheel chassis MAZ-7904. Created as part of the work on the Tselina project. The carrier for a promising missile system was built in Minsk in a single copy. The Tselina project was a response to the emergence of new American intercontinental ballistic missiles and the result of another round of world tension between the Soviet Union and the United States. The machines created as part of the Tselina project remained secret developments for many years.
The experimental car was completely ready and built in 1983, which received the factory index MAZ-7904. The giant’s own weight was 140 tons. The total carrying capacity was estimated at 220 tons. The total weight of the car with a load exceeded 360 tons. The total length of the six-axle vehicle exceeded 32 meters, the width was 6.8 meters, and the cabin height was 3.45 meters. Ground clearance 480 mm. On the front overhang of the MAZ-7904 frame, the designers carried out two fiberglass cabins designed for two people. The new chassis received three two-axle bogies, which were the base for 12 wheels. The wheel diameter was 3 meters. Tires were purchased in Japan from Bridgestone. Each wheel accounted for up to 30 tons of complex weight.
The ship’s diesel engine of the V-shaped 12-cylinder diesel engine ChN18/20 became the heart of the car. The engine developed a maximum power of 1500 hp. Additionally, another diesel engine was installed – a V-shaped 8-cylinder turbocharged YaMZ-223F, which produced a maximum power of 330 hp. The second engine was used as a drive. The main engine was installed between the two cabins. The power plant actuated two four-speed hydromechanical transmissions, which transmitted torque to the three front and three rear axles of an unusual car. According to the project, four wheels of the front and rear carts were controlled, and the approximate turning radius of the car was 50 meters. Each of the 12 wheels was mounted on a hydropneumatic suspension.
After the completion of the test cycle, the car was sent to Baikonur. The second phase of testing began in the Kazakh steppes. The vehicle was now tested with a maximum load simulator on board. Such tests quickly helped to identify shortcomings. The main thing was a lot of pressure on the ground – each axle accounted for up to 60 tons. For this reason, the tractor showed low off-road patency. Tests also showed poor handling. It was decided to cancel the project.