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 and support it with jackstands. Refer to Lifting and Jacking the Vehicle .
Fig 1: Identifying Special Tool - 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 straight-ahead and install anti-rotation pin J 42640  .
3. Install runout gauge J 45101  between the idler arm and the vehicle frame.

   Ensure the runout gage is at zero before taking the measurement.

Fig 2: Placing J 35999 Near Relay Rod End Of Idler Arm
Courtesy of GENERAL MOTORS CORP.
4. Place scale J 35999  near the relay rod end of the idler arm. See Special Tools .
Fig 3: Measuring 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 idler arm moves.
Fig 4: Measuring Idler Arm Movement (Relay Rod End)
Courtesy of GENERAL MOTORS CORP.
6. If the movement exceeds 2 mm (0.078 in) then replace the idler arm.
Fig 5: View Of Dial Indicator At Idler Arm
Courtesy of GENERAL MOTORS CORP.
7. Install the runout gauge at the idler arm.
8. Push the tire inward slowly with one hand to remove any lash.

   Zero out the runout gauge 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 the movement is more than 1 mm (0.039 in) then replace the idler arm.