A large part of BMP-2 Infantry Fighting Vehicles needs to replace turret ball bearing rings. Under realization of replacement of spare parts and components made in Russia with domestic ones, KNVO "Fort" MVO Ministry of Internal Affairs of Ukraine made an experimental batch of balls for turret ball bearing rings of infantry fighting vehicles BMP type. As a result of modernization of a turret ball bearing ring, steel balls were replaced with balls made of composite material.
 A turret ball bearing is a large radial thrust bearing, cages of which are turret races. A stabile lower race is fixed by means of screws to a top of the vehicle‟s hull. Above the fixed race there is a movable upper race to which the turret is bolted.
 A method for assessing the reliability of turret ball bearing rings of military armored vehicles was developed. The results of tests of turret ball bearing rings of BMP-2 infantry fighting vehicle tower are given. The reliability of turret ball bearing rings of armored vehicles was assessed taking into account the damage to the balls. The main types of damage to the balls: non-compliance of balls average diameter and non-compliance of the spherical shape of the ball to the requirements of operating documentation. The impact of the probability of no-failure operation of the balls on the durability of the ball bearing is determined.
 It is necessary to take into account the presence of damage to the balls when determining the durability of the ball bearing. To validate the adequacy of the method, it is necessary to increase the test time of the ball bearing by conducting tests during its operation.