A mathematical model that allows comprehensive calculation of hydraulic hitched system (HHS) operation of a four-wheel gantry tractor with high clearance was developed in the paper. Analytical dependencies of angles, angular velocities and angular accelerations were determined, as well as the analogs of linear and angular velocities and link accelerations based on the kinematic diagram of the HHS hitch mechanism. A method for complex calculation of the HHS and a computer program using the Pascal algorithmic language were proposed on the basis of developed mathematical model. The changes in values of the driving force and re-sistance force on the hydraulic cylinder rod and the changes in fluid pressure in the hydraulic cylinder were calculated.

Universal-plowing wheeled tractors are operated in two fundamentally different modes: in-ter-row machining, where driving precision and minimum turning radius are decisive, and transport operations, where stability and smoothness of movement come to the fore. The trans-formed driving system, which allows for changing the base, track, and clearance (and conse-quently, the agrotechnical or road clearance), allows for adjusting the geometry of the driving system to the operating mode; however, the influence of these parameters on the oscillations of the frame has been studied in fragments. The work analyzed an array of 545 publications downloaded from the Scopus database on September 21, 2026, on the topic of vibrations of tractors and off-road vehicles. It is shown that 73% of the documents were published after 2010, and the research focuses on operator vibration protection, seat and cabin suspension, and tire dynamics, while works where base, track, and clearance are considered simultaneously variable parameters are rare, and there are no publications on tractors with a transforming chassis in the sample. To fill this gap, a mathematical model of the tractor's plane oscillations was constructed based on Lagrange equa-tions of the second kind, taking into account the non-holonomic connections of wheel rolling, and characteristic equations and expressions for low-frequency and high-frequency components of natural oscillations were obtained. Modeling at 245 cm and 275 cm bases, corresponding to tractors for row tillage and transport work, showed that as the speed increases, the oscillation amplitude increases and the period decreases, while increasing the tractor base decreases the amplitude. Tests of the TTZ-1033M tractor prototype with ADXL345 accelerometers at a track gauge of 1200–2400 mm and a clearance of 650–870 mm confirmed these dependencies: the increase in clearance in-creases vertical vibrations, the increase in base decreases them, and the change in track mainly determines the difference in rear wheel vibrations. The practical conclusion is that it is advisable to have a short tractor base for row-crop cultivation and a long tractor base for transport work.