The vehicle has improper strut dampener action.

Service and/or replace as needed.

Refer to Strut, Strut Component, and Spring Replacement .

The vehicle has excessive tire/wheel runout.

Inspect the components.

Refer to Tire and Wheel Vibration in Vibration Diagnosis and Correction.

The tire/wheel is out-of-balance.

Balance as needed.

Refer to Tire and Wheel Balancing in Vibration Diagnosis and Correction.

The tire has a blister or bump.

Replace the tire as neccessary. Refer to Tire Mounting and Dismounting in Tire and Wheels.