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The powersplit transaxle is a key subsystem of Ford Motor Company's hybrid electric vehicle line up. The powersplit transaxle consists of a planetary gear, four reduction gears and various types of bearings. During vehicle operation, the transaxle is continuously lubricated by a lube oil pump. All these components consume power to operate and they contribute to the total transaxle losses which ultimately influences energy usage and fuel economy. In order to enable further model-based development and optimization of the transaxle design relative to vehicle energy usage, it is essential to establish a physics-based transaxle model with losses distributed across components, including gears, bearings etc. In this work, such a model has been developed. The model accounts for individual bearing losses (speed, torque and temperature dependency), gear mesh losses, lube pump loss and oil churning loss.