The transmission gearbox housing is the load-bearing and protective casing of a gearbox, cast in cast iron or aluminum with material chosen by transmission type (manual, automatic, CVT). Its interior carries precise gear-shaft bearing bores, shift mechanism cavities and oil passages that locate the gear set and shift mechanism. The housing offers high rigidity to resist the torque and impact loads of gear meshing, while sealed joint faces prevent lubricant leakage. Aging treatment relieves casting stress and external heat-dissipation structures assist cooling, matching the powertrain and space of different vehicles.

Because gear noise depends on bearing-bore coaxiality, buyer value comes from machined alignment across repeat batches: we cast the housing from drawings and machine bearing bores to tight coaxiality and parallelism, using aging treatment to keep the casting stable. Producing the housing to a defined transmission family means successive units keep gear mesh consistent, which is what buyers need when sourcing replacement or series gearbox cases.