A spacer apparatus for insulating a beam bushing assembly of an axle/suspension system from direct metal-to-metal contact with the vehicle frame hanger on which the assembly is pivotally mounted. In one embodiment, an integrally-formed one-piece apparatus includes a spacer disk portion and collar portions, whereby the collars provide a complementary fit of the spacer apparatus on the bushing assembly mounting tube, and generally prevents or minimizes relative movement between the spacer disk and bushing assembly. In other embodiments, one or more load dissipation structures mounted on or forming a part of the beam and/or its bushing assembly prevent substantially non-planar surfaces of the assembly from contacting a spacer disk by increasing the bearing area of those surfaces which contact the disk. These apparatus generally eliminate excessive wear or damage to the spacer disk and possible resulting damage to the axle/suspension system.