A top load liquid filter assembly includes a filter lockout mechanism to ensure that the filter base and cover are not connectable unless there is a proper filter cartridge installed therein. The filter system can also include an automatic drain mechanism and a cartridge retention mechanism. One example embodiment further includes an air bleed vent. A filter cartridge usable in the topload liquid filter assembly includes first and second protrusions and cover-gripper members. Methods of use, installing, servicing, and retaining can be practiced.