Vibration Theory and Terminology: Order

WARNING: This page is about a different car, the 2007 Suzuki XL7. However, it is still accessible from the selected car via links, so may be relevant.

Order refers to how many times an event occurs during 1 revolution of a rotating component.

Fig 1: View Of First Order Tire Revolution Vibration

Courtesy of SUZUKI OF AMERICA CORP.

For example, a tire with 1 high spot would create a disturbance once for every revolution of the tire. This is called first-order vibration.

Fig 2: View Of Second Order Tire Revolution Vibration

Courtesy of SUZUKI OF AMERICA CORP.

An oval-shaped tire with 2 high spots would create a disturbance twice for every revolution. This is called second-order vibration. Three high spots would be third-order, and so forth. Two first-order vibrations may add or subtract from the overall amplitude of the disturbance, but that is all. Two first-order vibrations do not equal a second-order. Due to centrifugal force, an unbalanced component will always create at least a first-order vibration.