Expedition; 4WD; Rear. Expedition; RWD; Rear. Navigator; 4WD; Rear. Navigator; RWD; Rear. Drive Shaft Slip Yoke. Flexible Coupling used to transmit rotational torque between the Drive Shaft and the flange. DriveShaft CO. DriveShaft Flag. FLANGE. Flexible. Prop Shaft Flex Joint. Prop Shaft Slip. Included with: Drive Shaft, Drive Shaft Order by application, Drive Shaft assembly.