Abstract: Disclosed is a system and method for accurately balancing a wheel/tire assembly. The assembly is mounted onto a shaft of a dynamic wheel balancer to rotate therewith. The shaft and wheel/tire assembly are spun while the balancer senses and stores a first set of information (readings) indicating imbalance. Next, the wheel/tire assembly is released and reoriented at a different angle, for example 180 degrees, on the shaft of the balancer, followed by respinning the wheel/tire assembly while the balancer takes a second set of readings indicating imbalance under these changed conditions. The values of both sets of readings are stored and then compared to note the difference therebetween. The difference represents a measure of the aggregate actual and "apparent" imbalance. For example, if the reorientation is 180 degrees, then the difference will be twice the actual imbalance. If the reorientation is less than 180 degrees, then the difference will be proportionately less than twice the actual imbalance.

Abstract: A wheel alignment and ball joint wear monitoring system employs a diagrammatic pictorial video display of the chassis of the vehicle being aligned and pictorial diagrams of alignment parameters associated with each of the wheels of the chassis. The region of each wheel when separately enlarged carries a chassis diagram indicating which wheel portion of the diagram has been enlarged. The system permits successive measurements of camber and of toe to be used to determine ball joint wear in the vertical and horizontal planes.