With the increase in electrified traction applications, high performance electric motor drives are now frequently coupled to gear transmissions in vehicles. It is appropriate to note that these drives have the capability to be used as a built-in sensor to estimate important characteristics of the mechanical system. The techniques to do this proposed in this paper do not require any change in the motor drive sensors, and can be performed in real time during continuously changing conditions. By estimating the states of each element as a function of its position, spatial synchronous averaging can be used on each element to identify its unique characteristics, including deterioration. This paper presents the development and evaluation of these technologies, and an exploration of the limitations of the proposed technologies.