In non-shiftable designs with a fixed gear ratio, spur-gear planetary trains are used as wheel hub transmissions. In this way, the torque that acts on the drive shafts of the driven axles can be lowered and the radius of the shaft can be reduced. Despite the transmission being positioned in the wheel area, this leads to a reduction of the unsprung masses. Using the two-level ratio, distinctly reduced "short" axles can be realized, e.g. for construction site vehicles. Furthermore this leads to economy of space as a consequence of the smaller differential ring gear due to the smaller ratio required on the differential transmission. A disadvantage is the unavoidable reduction of efficiency due to the multi-stage reduction. The spur-gear transmission is only used in commercial vehicles.
The planetary transmission is also used as a transfer case or add-on transmission (in high power transmission designs). None of the center shafts of the epicyclic transmission are fixed. In the transfer case, the input torque is distributed into two outputs. In an add-on transmission, an input torque can be added on to an output torque. However, in this case, the epicyclic transmission is no longer a torque converter since the supporting torque is absent.