Payload measurement system for machine with hauling body

A payload measurement system can be used to measure the payload added to a machine supported on a plurality of walking beams. A plurality of load cell sensors is mounted to the walking beams in locations where, when the walking beam bends, the sensors are placed under load. The load cell sensors include a symmetrical strain bar having first and second mounting ends connected by a connecting span, wherein the end thickness is greater than the span thickness of the connecting span. The connecting span is disposed between and spaced apart from an upper plane and a lower plane with which the surfaces of the mounting ends are aligned.