D151073 bushing lower swing tower pivot, top Fits Case 580L, 580SL, 580M, 580SMOne New Aftermarket Replacement Lower Swing Tower Pivot Bushing (Top) for Case Backhoe Loaders This bushing fits the lower swing tower pivot (top position) on Case backhoe loaders, providing a precision wear surface at the critical pivot point where the swing tower connects to the frame. One bushing required per machine. Also sold as part of the Case swing tower pin and bushing kit (326806A1 KIT). Specifications Inside Diameter (I. D.): 2. 76 in. (70.