- Raise and suitably support the vehicle with safety stands. Refer
to 
Lifting and Jacking the Vehicle 
in General     Information.
 
- Allow the front wheels to rotate freely.
 
- Allow the steering mechanism to turn freely.
 
- Position the wheels in a straight ahead position.
 
- Position a dial indicator against the top of the idler arm grease
cap.
 
- Place a spring scale near the relay rod end of the idler arm.
 
Important: 
|    •  | Do not forcefully move the right tire and wheel assembly back
and forth in order to cause an up and down movement of the idler arm. | 
 
|          | There is no control on the amount of force being applied to the idler
arm. | 
 
|    •  | Vehicle shimmy is not always caused by a loose idler arm. | 
 
|          | Before suspecting suspension or steering components, consider the following
areas: | 
 
|       -  | Force variation of tire and wheel assemblies | 
 
|       -  | Road surface irregularities | 
 
|    •  | Refer to Tires and Wheels and Vibration Diagnosis and Correction. | 
 
- Apply 110 N·m (81 lb ft) of force upward
and then downward while measuring the total distance that the arm moves.
 
- Measure the total distance the idler arm moves under the applied
force specified. Allow no more than 3 mm (1/8 in) deflection
  in each direction, for a total of 6 mm (1/4 in).
 
- Replace the idler arm if it fails this test. Refer to 
Idler Arm Replacement 
.