Here’s a great article on eliminating noise created by an alignment pin of a Kia Optima.

This article provides information related to some 2012MY Optima (QF) vehicles produced from 2012MY SOP to November 14, 2012, Optima (TF) vehicles produced from July 15, 2011 to April 26, 2012, and Optima Hybrid (TF HeV) vehicles produced from May 14, 2011 to April 26, 2012 that may exhibit a creak or squeak type noise from the rear underbody during body flexing or torsion while driving at slow speeds. Before performing the repair, the concern should be duplicated by driving at parking lot speeds on uneven/bumpy pavement to induce body torsion and to recreate the noise. Note: This condition can also be replicated by rocking the rear of the vehicle side-to-side.

Service Procedure
Notice: A two-post lift must be used for this service procedure. A transmission jack will also be needed to lower the rear cross member.

  1. Remove both rear wheels.
  2. Remove the two rear upper shock mounting bolts (perform the repair one side at a time).
  3. Lower the rear cross member (1.5 inches) by loosening the cross member bolts (perform the repair one side at a time). Caution: Support the rear cross member by placing a transmission jack under the rear control arm before proceeding. Do not completely remove the rear cross member bolts, and only work on one side at a time.
  4. Locate the cross member alignment dowel pin.
  5. Use a reciprocating saw, pneumatic metal saw or equivalent to remove the alignment dowel by cutting near the base of the pin (10mm maximum from the base). Notice: Use a saw blade which is just long enough to reach the pin (5-inch blade). Be careful not to damage any other components. Caution: Be sure to use proper protective gloves/equipment when handling cut off tool.
  6. Remove and discard dowel pin.
  7. Apply zinc spray or cavity wax to exposed area(s) to prevent corrosion/rust of the bare metal.
  8. Torque the two rear cross member bolts. Cross member bolt torque specifications: 115-130 -lbs. (156.9~176.5 Nm)
  9. Reinstall and torque the rear upper shock mounting bolts. Shock bolt torque specifications: 36-63 -lbs. (49.0~63.7 Nm)
  10. Reinstall the wheel on the repaired side using the star torque pattern as indicated in the photo insert. Wheel lug nut torque specification: 65~79 -lbs. (88.3~107.9 Nm). Repeat steps 1~10 for pin removal on the opposite side of the vehicle.

To read the full Quality Connection Magazine article including additional information, specs, and illustrations for reference CLICK HERE.
Image Source