Downsizing Function Downsizing allows machine performance to be maintained even while reducing the installed drive power. In the ideal case downsizing results getting below the “magic” 56 kW limit for the diesel engine. In downsizing, the efficiency of the hydraulics is drastically increased and the available energy used more efficiently. The chief areas for optimization are the travel drive, the working hydraulics and the electronic control. With the downsizing system the available engine output was reduced from 68 kW to 55 kW while maintaining the same machine performance. This significantly reduced the challenges presented by the TIER 4 final emissions requirements. Example of a downsizing system from Rexroth on a compact loader