A shaft coupling for connecting an upper shaft with a lower shaft within a pumping system is designed to handle a large tensile load between the upper and lower shafts. In some embodiments, the upper shaft includes a shaft ring groove and the coupling has a body and a first receiving chamber within the body that receives an end of the upper shaft. The coupling also includes an upper internal groove extending into the body from the first receiving chamber and an upper split ring that is configured to be compressed into a position occupying both the upper internal groove and the shaft ring groove of the upper shaft. Set screws compress the upper split ring into the shaft ring groove of the upper shaft. In another embodiment, the coupling includes a plurality of locking screws that extend through the body into corresponding lock screw grooves in the upper and lower shafts.