Abstract: A hydrostatic vehicle drive system having a closed loop front wheel drive circuit and a closed loop rear wheel drive circuit with bi-directional pressure compensating crossover flow between the two closed loop circuits. Another hydrostatic circuit for driving auxiliary equipment also operates as a source of pressurized fluid for charging the wheel drive circuits. The auxiliary hydrostatic circuit includes priority flow to the auxiliary equipment and a flow control with pressure relief means to maintain a constant charging pressure and a predetermined fluid flow for operating the braking circuit as well as charging the wheel drive circuits.