Idler Arm Inspection

Tools Required

• J 35999  Spring Scale. See Special Tools .
• J 42640  Steering Column Anti-Rotation Pin
• J 45101  Hub and Wheel Runout Gage

1. Raise the vehicle on a hoist. Support the vehicle with jackstands. Refer to Lifting and Jacking the Vehicle .
Fig 1: Identifying J 42640
Courtesy of GENERAL MOTORS CORP.
NOTE: The wheels of the vehicle must be straight ahead and the steering column in the LOCK position before disconnecting the steering column or intermediate shaft from the steering gear. Failure to do so will cause the SIR coil assembly to become uncentered, which may cause damage to the coil assembly.
2. Position the wheels in a straight-ahead position and install the J 42640  .
3. Install the dial indicator J 45101  between the idler arm and vehicle frame.

   Ensure the gage is at zero before taking a measurement.

Fig 2: View Of J 35999 & Relay Rod End Of The Idler Arm
Courtesy of GENERAL MOTORS CORP.
4. Place a J 35999  near the relay rod end of the idler arm. See Special Tools .
Fig 3: Measuring The Upward Force
Courtesy of GENERAL MOTORS CORP.
5. Exert a 110 N.m (25 lb) force upward, and then downward while measuring the total distance the arm moves.
Fig 4: Measuring Idler Arm Movement (Relay Rod End)
Courtesy of GENERAL MOTORS CORP.
6. If movement exceeds 2 mm (0.078 in) replace the idler arm.
Fig 5: View Of Dial Indicator At The Idler Arm
Courtesy of GENERAL MOTORS CORP.
7. Install the dial indicator at the idler arm.
8. Push the tire inward slowly with one hand to remove any lash.

   Zero out the dial indicator and pull outward in order to take a reading.

Fig 6: Measuring Idler Arm Movement (Relay Rod End)
Courtesy of GENERAL MOTORS CORP.
9. Allow only 1 mm (0.039 in) of movement at the idler arm ball stud.

   If more than 1 mm (0.039 in) exists, replace the idler arm.

10. Lower the vehicle.