The Stilson two-piece, quick-disconnect floating cylinder rod coupler eliminates leak producing side-loads caused by the inherent out-of-squareness of most cylinders (or misalignment at assembly) by providing side clearance “float” between its male and female parts. It comes in two models. One provides axial lost motion for applications requiring impact, such as breaking loose wedge-type clamps. The other model provides minimal clearance for applications requiring axial positioning. It allows cylinders to be easily assembled to relatively inaccessible driven members because it is quickly connected (or disconnected) by side-wise movement between its male and female parts. It also allows driven members to freely rotate under load.