Features of functioning of the enterprises of car service at increase in seasonal demand for THAT and repair of motor vehicles are considered. For the analysis of their activity in the conditions of limited resources and a random flow of applications (requirements) the device of system of Queuing is applied

Keywords: Enterprise car service, the flow of requirements probability, criteria, costs, efficiency

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

On the basis of the mathematical apparatus of Queuing, a mathematical model for the diagnosis of the technical condition of vehicles with electronic control units. The developed mathematical model of vehicle diagnostics in the framework of discrete-event paradigm. Numerical experiments to assess the effectiveness of diagnostics are carried out.

Keywords: cars, electronic control unit, diagnostics, Queuing system, efficiency, operating costs

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 study on the hardness of samples from steel ST3 and 15G. On the basis of the correlation equations obtained values of ultimate strength of the examined steels. With the application of the law of three-parameter Weibull distribution constructed density distribution and the resulting minimum value of ultimate strength. The obtained results are proposed to use to determine the value of the resource for load-bearing systems of vehicles.

Keywords: reliability, lifetime, the hardness of steel, strength of steels, the endurance limit of steels, the Weibull law

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