Gears are of the most common power transmitter in industries. Due to the issues which may be resulted from shocks and stresses in gearboxes, these equipment are exposed to special failures. In some cases too many gears are used in a gearbox which cannot be diagnosed easily. A vibration analyst needs to know about all gear types, designations, calculating formulas and etc. Some of the effective parameters on vibration in a gearbox are related to design consideration that should be under the supervision of vibration engineer to take them in to account. The number of gear tooth and the effect of common factor on the gearbox vibration is of these factors. In gearbox failure training course, the introduction of gears types, design consideration, failure diagnosis and other common problems are reviewed. Course outline is accessible in download section.