A wheel balancer includes a shaft adapted for receiving a wheel/tire assembly. The balancer has a longitudinal axis and is rotatable about the axis so as to rotate the wheel/tire assembly removably mounted thereon. A sensor assembly is provided for measuring rotation of the shaft about the longitudinal axis. A vibration sensor assembly measures vibration of the wheel/tire assembly as the wheel/tire assembly is rotated. A motor operatively connected to the shaft rotates the shaft about the longitudinal axis, thereby to rotate the wheel/tire assembly. A load roller applies a generally radial force, which can exceed one hundred fifty pounds, to the wheel/tire assembly during rotation of said wheel/tire assembly. A sensor detects lateral force, wheel/tire assembly radius, and/or wheel/tire assembly diameter, which can have a tendency to cause a vehicle on which the wheel/tire assembly is mounted during use to deviate from a straight line path. A control circuit responsive to the measured vibration of the wheel/tire assembly determines wheel imbalance, and is responsive to the measurement of lateral force, assembly radius, and/or assembly diameter to provide information relating thereto to a user.