Diagnostics of bearing assemblies during operation are essential for maintaining operational reliability. The study focused on the bearing assemblies of the rear axle gearbox of a KAMAZ 6×4 vehicle. Finite element modeling of temperature distribution was performed using APM FEM. An INSTRUMAX PIRO-330 pyrometer and a UTi260B thermal imager were used to measure temperatures. Digital twins of the bearing assemblies were developed to obtain friction zone temperatures and proportionality coefficients for the finite element models, based on the nominal load criterion and lubricant properties. Thermal imaging demonstrated the practical applicability of digital thermal diagnostics technology and the developed digital twins. Practical recommendations are proposed for technical diagnostics of bearings using infrared pyrometers, thermal imagers, temperature indicator stickers, and a transmission fault recorder.

Transmission, Technical diagnostics, Thermal diagnostics, Controllability, Bearing, Finite element analysis, Gearbox

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