Lightweight forged differential

Lightweight forged differential

Forged instead of cast part

Differentials are found in all vehicles – in four-wheel drives there are even two of them. They are mostly designed as a hypoid-toothed ring gear or as an input gear with helical teeth on the outside. Both types are connected to a cast housing. This can lead to geometry duplications (e.g. for fastening) which increase the system mass. Hirschvogel opts for a forged component area which can be designed very thin due to the high Young’s modulus and the high strength of the steel. Welding the part to a ring gear or speed gear (whose central area then forms the cover of the differential housing) leads to significant weight savings compared to conventional solutions.


Application Area

  • Powertrain
  • Differential


Case-hardening steel for toothed part, bainitic or dispersion-hardening steel for housing component; both materials have good weldability

Production Process

Forging, machining, heat treatment, joining


Lightweight solution beyond conventional approaches