A tensioning bar assembly for a drive system of an agricultural machine includes a longitudinal bar having a top end, a bottom end, and a threaded portion. An attachment device is coupled to the top end to attach to a tensioning arm. A compression spring is located around a portion of the longitudinal bar. A first spring retainer engages with and retains a first end of the spring. A first locking nut fits to the threaded portion of the bar and retains the first spring retainer longitudinally in place relative to the bar. The longitudinal bar is rotationally freely coupled to the attachment device to permit free axial rotation of the bar about its longitudinal axis relative to the attachment device, and an engagement head is attached to and located at or proximate the bottom end of the longitudinal bar for engagement with a tool.