An improved assembly apparatus and method of assembling workpieces together. The apparatus includes a drive linkage with a linearly movable ram for pushing one workpiece toward the other. The drive linkage also includes a rotatable drive train. In the improved assembly apparatus, a transducer is provided to determine the load existing in the drive linkage, and a resolver is provided to determine the stage of the assembly cycle. A programmable controller is used to correlate this information, and a device is provided for communicating a message related to the correlated information. The transducer may be a strain measuring device or a pressure transducer measuring the pressure in an hydraulic cylinder in the drive linkage. The communications device may be a visual monitor, alarm, recording device, or similar communicator. The system may include a data storage device to receive information on the preferred load or range of loads so that the programmable controller may retrieve this data and compare it to the existing load and warn of or record any undesirable deviation.