The paper analyzes the influence of such indices as current cylinder capacity, working body mass during gas exchange, supply of heat emitted during fuel combustion and heat exchange with walls within cylinder on pressure quantity in the cylinder. Structure of the new calculation formula for time of mixture combustion delay is developed.

The paper deals with improvement of previously developed calculation methods for criteria of static (critical angles of sliding and roll-over) and dynamic (critical speeds of beginning of skidding and beginning of roll-over on corner) tricycles stability.

Known energy efficiency indices of wheeled vehicles are analyzed, new indices having distinct advantages compared to known ones are proposed. The advantages are unambiguity of physics of proposed indices, their informativity and usability in the solution of problems of optimization and designing of “smart” transmissions of multi-drive wheeled vehicles.

It is shown that automatic control system of grain mass threshing used in field or in stationary conditions will decrease rack, sieve and cylinder losses of grain, will ensure stable operation of suction conveyor.

Data obtained from an experimental research of electric drive with molecular energy storage permits to conclude that using of the capacitive storage as a part of electromechanical transmission is appropriate. Proposals concerning organization of automated system of motion control for a tracked vehicle equipped with electromechanical transmission using molecular energy storage are developed.

Specific features of application of biofuels with soybean oil in diesel engines are considered. Results of experimental research of Д-245.12С vehicle diesel engine operating on diesel fuel and soybean oil mixtures are given. Dependence of fuel economy and exhaust gases toxicity characteristics on mixed biofuel composition is shown.

Disadvantages of grain dryers are indicated. The method for elimination of the disadvantages by means of grain layer inverter installation is proposed. Description of the inverter and results of researches of grain drying process in chamber louver-type grain dryer with inversion and without inversion of grain layers are given.

Results of prospects investigation of dynamic oscillations absorbers using in suspensions of tractor cabs are described. Design of dynamic absorber is developed and patented. On the basis of calculation and experimental research, it is shown that in practice under all modes of moving of tractor unit, the cab springing system with dynamic absorbers ensures the best protection of operator position against vibration in comparison to systems with serial rubber vibration isolators.

Dependence of intra-cyclic acceleration of crankshaft rotation under steady-state mode on disbalance of engine is revealed. On basis of this dependence, the method for estimation of imbalance of machine engine without disassembling is developed.

The article is dedicated to 65th anniversary of production start-up of widely known ДТ-54 tractor. Principal stages of its improvement and modernization are given.

The method for determination of systematic errors during dynamometry of different working organs of tillage tools is proposed.