A suspension for a heavy duty vehicle is provided that includes a frame. A lower linkage is supported by the frame at a first pivotal connection. A drive axle assembly is supported by a lower linkage at a second pivotal connection. The drive axle assembly includes an input shaft defining a pinion angle. An upper linkage interconnects the drive axle assembly and the frame at third and fourth pivotal connections, respectively. The upper linkage includes an adjustment member, such as a turnbuckle, for modifying the length of the upper linkage to obtain a predetermined pinion angle. In this manner, the pinion angle may be adjusted upon assembly of the suspension system. Furthermore, by permitting the drive axle assembly to pivotally move relative to the linkages, the pinion angle may be maintained during suspension movement.