Economic-probabilistic method assesses the feasibility of tactics for MAINTENANCE and operating time and technical condition for buses equipped with electronic control units. The scheme of determination of limit values of diagnostic parameters is proved. It is shown that the implementation of the STATE is appropriate when the economic costs associated with the cost of diagnosing and forecasting the technical condition of the buses are not decisive.

Keywords: strategy, tactics, method, parameter, maintenance, repair, cost, reliability, operation, technical condition

The possibilities of theoretical and experimental methods for determining the rheological characteristics of technical fluids are explored. A comparative evaluation of rotational and gyroscopic viscometers was carried out. The phenomenon of slippage of layers of non-Newtonian fluid at the surface of measuring cylinders is revealed with increasing gradients of shear rates and filler content.

Keywords: Technical fluids, non-Newtonian environment, rheology, viscometer, rheological model, automotive engineering

The methods for determining the standards for the preventive maintenance system and repair are analyzed, it is found that the current norms are essentially outdated and require revision at the federal level. It is shown that the specifications for maintenance and repair specified by the operating time for modern cars should be revised in favor of standards determined by their condition, which will allow the introduction of individual standards for each car, taking into account the operating conditions and its technical condition.

Keywords: Strategy, method, standard, parameter, maintenance, repair, maintainability, mileage, reliability, operation

The peculiarities of the activity of mobile car repair shops are considered. Mathematical models for determining indicators, taking into account the randomness of the receipt of requirements for maintenance and the duration of the services themselves, are proposed.

Keywords: mobile car repair shop, probability, criteria, complex indicator, efficiency