A module for a frame for a motor vehicle and a method of forming a frame assembly with a pair of laterally spaced, longitudinally extending central side rail structures includes, in one embodiment, using a pair of tubular hydroformed side rail members and a laterally extending connecting structure connected between the pair of side rail members to secure the pair of side rail members in laterally spaced, fixed relation to one another. Each first portion of the pair of side rail members extending longitudinally and each second portion of the pair of side rail members extending laterally relative to the respective first portion and each second portion having an end being constructed and arranged to form a joint with a portion of a respective central side rail structure such that the end of each of the pair of side rail members extends generally laterally through a side of the respective central side rail structure.