A high clearance, variable load transfer axle assembly is mounted between the forward steerable and rearward drive wheels of a transit mixer truck to selectively support a portion of the weight of the truck and its load. A drive shaft extends longitudinally beneath the truck to the rearward drive wheels, with the load transfer assembly having an auxiliary frame pivotably mounted adjacent its forward end to the truck's main frame beneath the drive shaft. Wheels are mounted on a laterally extending axle member of the auxiliary frame, and the auxiliary frame pivots on a lateral axis relative to the truck's main frame between a raised position and a lowered load support position. Variable force applicators positioned between the auxiliary frame and the truck's main frame control the pivoting of the auxiliary frame between these two positions. The laterally extending axle member is formed with a drop center portion to accommodate the drive shaft of the vehicle when the auxiliary frame is in the raised position relative the truck's main frame. The auxiliary frame has a plurality of pivot guides to limit lateral movement of the auxiliary frame relative to the vehicle.