A filter monitoring system and method are described. The filter monitoring system includes a module or circuit installed on an internal combustion engine or within a vehicle powered by the internal combustion engine. The filter monitoring system monitors the operation of the various filtration systems present on the engine to determine an amount of service life remaining and a loading percentage for various filter cartridges installed in the filtration systems of the internal combustion engine. The filter monitoring system determines the loading percentage and predicts remaining service life of a given filter cartridge via a time-based manner (e.g., based on the installation date of the filter cartridge and filter cartridge life specifications) and a pressure differential based manner (e.g., based on a determination of pressure drop across the filter cartridge).