Railcar monitoring utilizes instrumented, flexible pads supported within the truck pedestal jaws on the bearing adapters. The pads contain sensors for monitoring temperature pressure, shifting loads, truck hunting and the like and have circuitry for processing information received from the sensors and for processing and reporting departures of performance variables to a remote source. The system cyclically activates polling each pad on a car and communicates signals of critical departures and car identity to a remote source.