Road Test

Road test vehicle on a smooth road for a least five miles to warm tires (remove any flat spots). Lightly place hands on steering wheel at the 10:00 and 2:00 positions while slowly sweeping up and down from 90 to 110 km/h (55 to 70 mph) where legal speed limits allow.

Observe the steering wheel for:

• Visual Nibble (oscillation: clockwise/counterclockwise, usually due to tire imbalance)
• Visual Buzziness (high frequency, rapid vibration up and down)

To rule out vibrations due to brakes or powertrain:

• Lightly apply brakes at speed; if vibration occurs or is enhanced, vibration is likely due to causes other than tire and wheel assemblies.
• Shift transmission into neutral while vibration is occurring; if vibration is eliminated, vibration is likely due to causes other than tire and wheel assemblies.

For brake vibrations. Refer to Brakes/Hydraulic/Mechanical/ROTOR, Brake - Diagnosis and Testing .

For powertrain vibrations, refer to DIFFERENTIAL AND DRIVELINE .

For tire and wheel assembly vibrations, continue with this diagnosis and testing procedure.