Car wheels are operated in difficult conditions. The system of forces and torques acting on the wheel is determined by many factors: transfer of energy from the engine through the transmission to the wheel, environmental conditions, and the driver’s control actions. During the work, previously developed and implemented tire calculation methods and experimental methods for operational tire testing were used. The purpose of the work is to determine the main design parameters for the theoretical study of a passenger car pneumatic tire under operating conditions and a mathematical model. The main calculated dependences of the stiffness, deflection and contact length parameters of the pneumatic tire of the vehicle are considered. The theory of thin flexible shells with large deflections was chosen to solve the research problem. The model of the crown part of the tire, with the upper part of the frame, the breaker and the tread is made in the form of a rigid in the transverse direction and flexible in the circumferential direction of the tape. The initial data for the calculation are the design parameters of the tire, air pressure and normal load. Laboratory data and many published papers show that when the wheel is loaded with a normal force, the stresses in the middle of the peripheral surface of the tire remain virtually unchanged, i.e. they are equal to the displacements and stresses caused by internal pressure. As a result of the work, the main results were obtained by calculation and experimentally. It is determined that under the influence of a normal load and the resulting displacement of the elements of the tire crown, the specific force decreases in the circumferential direction, which corresponds to the experimental data.