A car exhibits bad characteristics when the wheels are bent — it will shake at highway speeds, the steering wheel may shimmy or the car may "buck," like a bucking bronco. How far off-center the wheel is bent is called runout. All these symptoms point to one of two types of runout, or a combination of both. By understanding both types of runout for wheels, you will understand the specifications as well.
If you hit a curb sideways violently, the wheel more than likely will become bent. According to professional technicians at AA 1 Car, the side bending is called lateral runout. The chief symptom of lateral runout is that the car shimmies or shakes. The shaking becomes more violent as the car goes faster.
Theoretically, wheels should have no lateral runout. Professional technicians at Vibrate Software state that the lateral runout should be no more than .045 inches. Professional Technicians at the Inter-Industry Conference on Auto Collision Repair state that most manufacturers specify a lateral runout of no more than .1 inches. To put these numbers into perspective, the wheel cannot be bent sideways more than the thickness of a pencil lead.
If you hit a pothole, more than likely radial runout will occur. Instead of the wheel being perfectly round, it acquires an oval shape. The chief symptom of radial runout is the car "bucks," like a horse bucking. This is because the wheel has low and high spots. The bucking becomes more violent the faster the car goes.
Theoretically, the wheel should be a perfect circle, with no high or low spots. Technicians at Vibrate Software specify a radial runout of no more than .04 inches. However, the technicians at the Inter-Industry Conference on Auto Collision Repair state a radial runout of no more than .06 inches. These numbers are very small. In essence, the wheel cannot be out of round by more than the thickness of a thin pencil lead.
The only real cure for steel wheels is to replace it with a new wheel. High dollar aluminum or custom wheels are usually repaired by a facility specifically designed to unbend wheels. The cost to repair a wheel, however, is prohibitive. For a high dollar wheel, the repair cost is less than buying a new wheel. For a steel wheel, however, it's often cheaper to just buy a new wheel, with has no runout.
