Powertrain module for zero turn radius vehicle

The present invention relates to vehicles such as lawn and garden tractors and riding lawn mowers used in the lawn and garden industry, particularly lawn mowers of the zero turn radius variety which include hydrostatic transaxles and which are steered by controlling the speed and direction of the ground-engaging drive wheels of the mower. A powertrain module for a zero turn radius vehicle, such as a tractor or mower, the powertrain module generally including a structural member or mounting plate to which an engine, a pair of hydrostatic transmission modules, and a pair of axle drive units are attached to form a self-contained powertrain module which may be shipped as a single packaged unit for installation into the zero turn radius implement. The mounting plate provides structural rigidity between the powertrain components attached thereto, and the mounting plate of the powertrain module may be attached directly to the frame of the vehicle, or alternatively, may itself serve as a structural frame member for the vehicle.