A drive and control system is provided for a towing vehicle pulling a towed implement, such as a tractor pulling a scraper. The drive system includes an engine which drives a generator for generating electric power. A towing vehicle electric drive motor is connected to driven wheels of the towing vehicle through a transmission. An assist or implement electric drive motor is drivingly connected to driven wheels of the implement. A power distribution unit controls distribution of electric power from the generator to the towing vehicle and implement drive motors. A control unit controls the power distribution unit as a function of an operator set power split, an operator set maximum wheel slip, sensed wheel slip and other sensed parameters.