Crossed helical gears belong to gear units with crossed wheel axles and in most applications consist of a steel worm and a plastic wheel. Due to the high transmission ratio in a small installation space, they are used in actuators, auxiliary drives and positioning drives. The research into high-performance polymers is accompanied by increasingly powerful gears, de pending on the properties of the plastic material, to reach the load limits of steel materials. Research on steel/plastic crossed helical gears with geometrically optimized tooth flank geometries offers efficiency improvements and demonstrable efficiency potential, enabling higher overall load capacities and an increase in service life. A more detailed resolution of the contact behavior in the contact area allows friction energies to be considered and provides the basis for local wear and load capacity evaluations. Based on this, new crossed helical gears with general flank geometries can be designed, which have a positive influence on resource conservation and sustainability as a result of the increase in lifetime.