Driving A Hydrostatic Transmission



Driving a hydrostatic transmission is a bit different than what many people are used to. With a hydrostatic transmission (HST), as your load increases (i.e. pulling a heavy load, operating with a loader in a dirt pile, pulling a trailer up a hill or operating in soft soil conditions) you want to maintain or decrease the pedal pressure as the load increases.  Do not "give it more gas" as it will cause the tractor to loose torque and/or cause the transmission pressure to raise and go into bypass. The increased oil flow from the HST pump gets dumped off as the relief valve opens.  This causes the HST motor to slow down. Maintaining the hydrostatic system's oil pressure within its operating range allows the motor to do the work more efficiently.  When operating in heavy load conditions it makes a huge difference to operate in the "lo" range, which also allows the HST to maintain lower pressures and work more efficiently. Basicly, think of the HST pedal as a gear shift. The harder you press it, the higher gear your in.