Abstract: A vehicle suspension system for mounting to a vehicle chassis includes a subframe which includes two tubular members. Each tubular member has a rear chassis mount and front chassis mount. The tubular member mounts are constructed and arranged to mount to a leaf spring mounting perch on the vehicle chassis. The tubular members are connected by a plurality of cross braces which in turn are connected to a plurality of intermediate tubes. A differential mount connects to a cross brace which is connected to a tubular member. An upper control arm mount and a lower control arm mount connect to intermediate tubes which are connected to a cross brace which in turn is connected to another cross brace. This all connects to at least one tubular member. A self-contained suspension assembly mounts to the subframe at various places. For example, a differential mounts to the subframe at the differential mount and a pair of half-axle shafts connect to the differential.