Dynamic stiffness is an important characteristic of production machinery, as it contributes to its ability to maintain the position of the tool centre point accurately and precisely under loads. For machine tools, it directly affects the geometric dimensions and surface properties of produced parts. This work presents a measurement procedure for identification of the full translational dynamic stiffness matrix for a single configuration of a machine tool under loaded conditions. The measurement procedure consists of inducing a static baseload with superimposed dynamic loads, which were controlled in magnitude and direction, at the tool centre point of the machine tool. The measurement procedure uses the Loaded Double Ball Bar and measures the dynamic displacement with three Non-Contact Capacitive Probes. The measurement procedure is implemented in a case study on a 5-axis machining centre. Finally, the manuscript concludes with a discussion on the utility value of the translational dynamic stiffness matrix for the design and operation of machine tools as well as the possibility to expand the measurement procedure to capture the dynamic stiffness using quasi-static movements of the machine tool.