Here is a W&R 10th Anniversary locomotive. The Southern Pacific MC-4 SP 4023 a 2-8-8-2 malley. An awesome engine that’s only been test run. It has a unique Delayed motion drive. It is equipped with a gearbox the permits the rear set of to turn independently before the other set of drivers begin to turn. The purpose is to attempt to duplicate the wheel slip that occurs on an articulated locomotive when starting a train. Please ask any question you may have.