In order to reduce the transmission’s squeak, the main noise source of the transmission is recognized by the NVH testing. By analyzing the dynamic actuation of gear clusters, it is confirmed that the mesh impact among gears is the main actuation source of the squeak. Then, by reducing backlash and increasing contact radio, the optimization of the gear clusters is carried out. This method is proved useful in reducing the transmissions squeak induced by the gear meshing.

Since the automobile industry has been developing continuously, noise control has already become a competitive focus in automobile companies. Gearbox is a key part of car, so noise control of gearbox is becoming more important. In this paper, DS2000 data collecting system of Onosokki Co. is used to collect a gearbox’s sound pressure signal. By making power spectrum analysis and order tracking analysis, the gearbox’s eigenfrequency and noise source could be found. This way is able to identify gearbox’s noise source, and has great wide application foreground.