It's the hybrid 5.7 hemi out of the new style rams, it has a bigger belt and an electric motor/generator driven by the belt bolted on the engine, it gives you some extra TQ when the battery is charged and switches to charging the battery when your coasting. They also have start/stop technology so they need to be able to start extremely quickly hence the funky teeth it has to know if the engine went backward at all on shutoff.