Idler Arm: Testing and Inspection

Important:
- Do not jerk the right tire and wheel assembly back and forth, causing an up-and-down movement of the idler arm. This is not an acceptable testing procedure because there is no control on the amount of force being applied to the idler arm.
- Use care whenever loose idler arms are suspected of causing shimmy complaints. Before suspecting suspension or steering components, consider the following areas:
- Dynamic imbalance
- Runout
- Force variation of tire and wheel assemblies
- Road surface irregularities
Refer to Tire and Wheel Vibration in Vibration Diagnosis and Correction under Steering and Suspension Testing and Inspection.

1. Raise the and support the vehicle. Refer to Vehicle Lifting.
2. Allow the front wheels to rotate freely and the steering mechanism freedom to turn.
3. Position the wheels in the straight ahead position.





4. Place a spring scale near the relay rod end of the idler arm (2).
5. Exert 110 N (25 lbs.) force upward and then downward (2) while measuring the total distance the arm moves.
The allowable deflection is 3.18 mm (1/8 inch) from the center for a total of 6.35 mm (1/4 inch) (1).
6. Replace the idler arm if the measurements are not within the specified range.