An axle assembly with an axle housing assembly and a differential that is mounted in the axle housing assembly for rotation about a first axis. The axle housing assembly defines an interior cavity with a sump having a static liquid lubricant level. The axle housing assembly includes a housing structure and a cover that is coupled to the housing structure. First and second sets of ribs are coupled to the cover and extend into the interior cavity. The first and second sets of ribs are disposed on opposite sides of a ring gear associated with the differential and include a plurality of ribs. A first portion of at least one of the ribs extends below the static liquid lubricant level to thereby be immersed when a liquid lubricant fills the sump to a level that coincides with the static liquid lubricant level.