During the Great Patriotic War, Soviet engineers revisited the idea of equipping tanks with gun stabilizers, based on their previous experience with the T-26, the BT-7M, and the American M4 Sherman. In 1943, they installed a stabilizer on a T-34 armed with the F-34 gun; however, tests that same year revealed poor reliability. By the time improvements were made, the T-34-85 had already entered service. Further stabilization work was carried out with this model in 1944. The stabilizer was designated STP-S-53, and five vehicles equipped with it were produced in 1945. In May 1946, trials began involving four modified T-34-85s. The results were positive; firing accuracy while moving at speeds up to 25 km/h increased by a factor of 2.5–3. A batch of 30 vehicles was proposed, as well as the design of a stabilizer for the T-34-100. However, both the 85 mm guns and the T-34 platform had already become obsolete, resulting in the termination of the program.

The T-34-85 (STP) was introduced in Update 2.51 "Spearhead". Apart from its single-plane stabilizer, it is identical to the standard T-34-85. This upgrade significantly improves combat performance by enabling accurate fire on the move. Though the gun’s penetration is insufficient for reliable frontal engagements, this is partially compensated by its strong post-penetration damage. Nevertheless, the armor of the T-34-85 (STP) remains inadequate, leaving the vehicle largely reliant on favorable ricochets.