In article service conditions of one of the most important systems of mobile cars – a hydraulic actuator, especially under the influence of the negative temperature of air are considered. Ways of prestarting heating and maintenance of temperature of working liquid in use of transport and technological mobile cars are described. The main advantages and the applied systems and devices come to light. The original system of regulation of temperature of working liquid in a hydraulic actuator which will allow to increase efficiency, reliability and accuracy of regulation of temperature is offered.

Keywords: hydraulic actuator, working capacity, negative temperatures, viscosity, friction, power, torque