Abstract: A steering gear rack (14) for a steering system (12) of a vehicle (10) is positioned in a housing (52) with its end portions (24, 26) protruding from the housing (52) to be connected by ball joints (32) and tie rods (16) to the front wheels of the vehicle (10). The hollow steering gear rack shaft (20) defines an air passageway (22) that extends between the end portions (24, 26). Each of the end portions (24, 26) has an end face (30) and internal threads (28) on the end portion (24) extending inward from the end face (30), and a longitudinal groove (34) extending inward from the end face (30) through and past the internal threads (28) and radially outward past the internal threads (28) extending the air passageway (22) to the end face (30). The end portions of the housing (52) are fitted with rubber boots (54, 56) to protect the ball joints (32) from the environment that are connected by the air passageway (22) and longitudinal grooves (34).