A modular hydraulic hammer reduction system for railroad tank cars includes tubular hydraulic hammer reduction devices which include means to connect the tubular devices to flanges other than by welding or being cast together. For example, the tubular devices can be press fit into the flanges, or the tubular devices can be connected to the flanges with snap rings (preferably spiral-lock snap rings), or even more preferably the tubular devices can be press fit into the flanges and the tubular devices can be connected to the flanges with snap rings (preferably spiral-lock snap rings). The advantage of this modular construction is that one can manufacture multiple tubular devices and multiple flanges of each type, and connect the flanges to the tubular devices on an as-needed basis. This is preferable to having many of each type of hydraulic hammer reduction system assembled and ready to be delivered, as the demand for different types of hydraulic hammer reduction systems varies and storing fully assembled devices will take up more space.