1. A method of determining a maximum oil change limit of an engine, the method comprising: providing a current location indicator of an engine to a controller in response to a current trigger; wherein the controller is configured to generate and store an oil change index and a maximum oil change limit; generating a current oil change index using the current location indicator and a current location rating; generating the maximum oil change limit of the engine using one of: the current oil change index, and the current oil change index and an at least one prior oil change index; and storing the maximum oil change limit using the controller.