LOAD SENSING VALVE

The load sensing valve regulates the braking pressure passing to the rear brakes so that maximum pressure is only available when the vehicle is fully laden. As the vehicle's load is reduced the valve automatically lowers the braking pressure

During the normal life of the vehicle the valve will require re-adjustment due to spring settlement (especially during its early life) at the periods shown in the service schedules


Taken from here http://www.dodge50.co.uk/service3.htm