An apparatus comprising an engine, a power take-off to be driven by the engine, one or more load services to be driven by the engine, a PTO modulator coupled to the power-takeoff output port and operable to selectively engage the power take-off to the engine to provide output rotational power, one or more load-service modulators coupled to the one or more load services and operable to selectively engage the one or more load services to the engine to provide service outputs, and a load controller configured to selectively operate the PTO modulator and the one or more load-service modulators to change the output from the power take-off or the one or more load services based on a condition of the engine and a load priority assigned to the power take-off or the one or more load services.