The T-43 was generally similar to the T-34, but had a new armour layout and turret design, a space-efficient torsion bar suspension instead of the T-34's Christie type, and a new five-speed gearbox. The first prototype T-43 was completed in March 1943. The T-43 project received low priority, as the primary focus was on increasing production of the T-34. T-34M had been cancelled in 1941, when Germany invaded the USSR. Uralvagonzavod included the Morozov Design Bureau, the designers of T-34, who were able to draw on its previous work on the advanced T-34M project. The Uralvagonzavod complex in Nizhny Tagil developed the T-43 medium tank. The SKB-2 heavy tank design bureau in Chelyabinsk started the KV-13 program, which two years later resulted in a line of successful Iosif Stalin heavy tanks.

In June 1942, the Soviet Main Directorate of Armoured Forces (GABTU) issued a requirement to two tank-design bureaus to compete in designing a 'universal tank', which would combine the heavy armour of heavy tanks with the mobility of the T-34 medium tank. In May 1942, Soviet forces started encountering German tanks armed with the new long 75mm KwK 40 gun which could easily penetrate a T-34 at long range. The T-34 medium tank was the mainstay of Soviet mechanized forces in World War II, produced in huge numbers.

Military tank turbosquid