Tire Run-Out
Run-out and out of round are terms used to describe when a tire or wheel assembly is not perfectly round, while balanced tires are tires that have been balanced to reduce the risk of uneven tread wear and other problems:
Run-out
Also known as out of round, run-out occurs when a tire or wheel assembly is not perfectly round. Run-out can be caused by a bent rim or uneven tire wear. There are two types of run-out
There are two types of tire runout: radial and lateral:
- Radial runout
This is when the distance between the tire's tread and the center of the wheel is not the same at every point on the tire. The greater the discrepancy, the more the wheel will bounce up and down as it rotates.
- Lateral runout
This is when there is sideways motion or "wobble" in the tire as it rotates. This can cause the tire to wiggle or vibrate and may also cause the car to veer erratically.
Runout can be caused by improper bead seating on the rim or by not match-mounting the tire and wheel assembly. Keeping tire and wheel assemblies balanced, and maintaining radial and lateral runout maximum specifications, can help reduce irregular wear and vibration.
