Abstract: A skid-steered tractor vehicle is driven by right and left hydrostatic transmissions having separate steering levers, one for each transmission. A centering device acting directly on the transmission controls is longitudinally shiftable against the force of a spring in response to pivotal movement of either steering lever from a neutral or idle position for returning the steering lever upon release. Also, there is a second pivotal mounting for one or both steering levers in a plane at right angles to the pivot axis of the levers for controlling auxiliary functions without interfering with the steering movements of the levers.

Abstract: A two-speed control for dual hydrostatic motors, especially for self-propelled, skid-steered loaders having hydrostatic transmissions. Each motor has a rotating piston group and a swash plate inclinable in either of two positions of piston displacement for low or high speed output. A shift lever connects the swash plate control arms of the motors with a manual selector lever biased by an over-center spring mechanism to either the high or low speed position. The shift lever has a slide and guide connection with one swash plate control arm and pivotally connects to the other in an arrangement which automatically locks the swash plates in the proper attitude in either shifted position of the slide and guide connection corresponding to the low or high speed range.Two variable displacement hydrostatic pumps, one associated with each motor, are independently controlled by a pair of control levers operable to vary the pump displacement within both the high and low speed ranges of the motors.

Abstract: A two-speed control for dual hydrostatic motors, especially for self-propelled, skid-steered loaders having hydrostatic transmissions. Each motor has a rotating piston group and a swash plate inclinable in either of two positions of piston displacement for low or high speed output. A shift lever connects the swash plate control arms of the motors with a manual selector lever biased by an over-center spring mechanism to either the high or low speed position. The shift lever has a slide and guide connection with one swash plate control arm and pivotally connects to the other in an arrangement which automatically locks the swash plates in the proper attitude in either shifted position of the slide and guide connection corresponding to the low or high speed range.Two variable displacement hydrostatic pumps, one associated with each motor, are independently controlled by a pair of control levers operable to vary the pump displacement within both the high and low speed ranges of the motors.