Gear noise is sometimes the dominating noise in commercial vehicles. Noise testing of complete gearboxes is very time-consuming and expensive. A test rig has been designed for testing gears under controlled conditions. The test rig is of the recirculating power type. Finite element analysis has been used to predict the dynamical properties of the gear test rig. Experimental modal analysis has been carried out on the gearbox housing to verify the theoretical predictions of natural frequencies. The test rig can be used for noise and vibration testing of gears with different manufacturing errors and different design parameters. In addition to noise testing, the rig can be used for gear life testing and measurement of efficiency.QC 2010092