The article suggests a simple method for estimating the weight of the cargo of a dump truck during its movement along the control section of the track, based on measuring the magnitude of the magnetic field induced by DC traction motors. To measure the magnetic field strength, a ferroprobe is used to convert the value of the magnetic field strength into the current value. As an indication device, an ammeter (milliammeter) is used, the scale of which is calibrated in units of mass. The engines of heavy-duty dump trucks generate a sufficiently strong magnetic field, so practically the place of installation of the ferroprobe does not matter - it is only important that it is the same, both when calibrating the milliammeter scale and when measuring. The proposed non-contact method for measuring the mass of cargo does not require complex technological equipment, and it reduces the time and cost of measurement, while providing sufficient accuracy.