Caution: Refer to Approved Equipment for Collision Repair Caution in the Preface section.

Important: 

Important: Sectioning of the lower rail does NOT require removal of the powertrain.

1. Visually inspect and repair as much of the damage as possible to factory specifications.
2. Remove all sealers and anti-corrosion materials as necessary.



3. Apply 25 mm (1 in) wide tape on the lower rail outer panel following the contour of the cowl.
4. Cut the outer panel along the forward edge of the tape. This will provide an overlap tab for welding the service part to the original rail without welding directly to the cowl panel.

Important: Welds on the engine cradle mounting bracket must also be drilled out to remove the outer panel.

5. Drill out factory welds attaching the outer panel to the rail inner panel. Do not drill through the inner panel.
6. Remove the rail outer panel.
7. Locate the 16 x 35 slot on the in-board side of the rail. Use the hole as a guide and mark a line on all three sides of the rail.
8. Cut the rail along the marked line and remove the damaged portion of the rail.

Important: Welds on the engine cradle mounting bracket must also be drilled out to remove the outer panel.

1. Separate the inner from the outer rail using an air chisel.
2. Remove the outer panel and set aside.



3. On the left inner rail service part, mark a line around the panel 30 mm (1 ¼ in) rearward of the 16 x 35 hole on the inner rail.
4. Use the hole as a guide and mark a line around the rail.
5. Cut the service part along the marked line and discard the unused section.



6. Cut a 3 mm (1/8 in) gap approximately 30 mm (1 ¼ in) deep along the corners of the inner rail to create tabs on the sectioned service part (1).
7. Step the tabs inward (2) to allow the service part section to fit inside the original rail.



8. Drill 5 holes for plug welding along the overlap approximately 13 mm (½ in) from the sectioning cut.
9. Position the modified service part inside the original rail.
10. Use three-dimensional measuring to align the rail.
11. Trim off the tab that attaches to the cowl panel on the rail outer panel.
12. Drill three 8 mm (5/16 in) plug weld holes along the overlap.

Verify that the engine cradle mounting location is in the proper position. Align and hand tighten bolt. Make 25 mm (1 in) stitch welds along the seam with 25 mm (1 in) gaps between. Go back and complete the stitch weld along the seam.

13. Position the outer panel and check for proper fit and alignment.



14. Stitch weld along the entire joint.
15. Plug weld all holes drilled during the removal process including holes drilled along overlapped areas.
16. Clean and prepare welded surfaces.

Important: Prior to refinishing, refer to GM 4901MD-99 Refinish Manual for recommended products. Do not combine paint systems. Refer to paint manufacturer's recommendations.

17. Install all related panels and components.