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Steering Input Test

This test is intended to determine how much the wheel bearings and other suspension components contribute to the vibration, especially a vibration relating to noise, such as growl, grinding, and roaring.

CAUTION: Refer to Road Test Caution in Service Precautions.

1. With the vehicle at the vibration speed (mph), drive through slow sweeping turns, first in one direction and then in the other direction.
2. If the vibration gets worse or if the vibration goes away, inspect the following components as possible causes of the vibration:
- The wheel bearings
- The hubs
- The tire tread
3. The CV joint angle increases when the vehicle is turning. On front wheel drive (FWD) and four wheel drive (4WD) vehicles, CV joint condition systems may appear when the angle increases. Putting a load on the CV joint may increase the vibration amplitude. The third order, tire speed related amplitude would remain the same.