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

Caution: Refer to Collision Sectioning Caution in the Preface section.

Important: When determining the area to perform the sectioning near a riv-nut within the recommended areas, choose a location that centers the sleeve through the hole. This will ensure that riv-nut fasteners remain straight during installation.

1. From the new section of frame rail, measure, mark, and cut 50-mm (2-in) of frame rail to be used as a sleeve (backing plate) for the sectioning joint.
2. Cut through each side of the sleeve to create 4 individual L-shaped pieces that can be installed in the existing frame rail.
3. Install the 4 pieces, one at a time.
4. Trim the pieces as necessary, to provide a flush fit along the inner surface of the existing frame rail.
5. Clean and prepare all of the welded surfaces.
6. Apply GM-approved weld-thru coating or equivalent as necessary. Refer to Anti-Corrosion Treatment and Repair .
7. Using a metal inert gas (MIG) welder, tack weld the 4 pieces to the inner surface of the existing frame rail.
8. Grind the sleeve as necessary to allow for accurate alignment of the new frame rail section.



9. Install the new frame rail section to the existing frame rail to create the butt joint while maintaining a gap of one and one half frame rail metal thickness at the sleeve butt-joint.
10. Inspect the new frame rail section using three-dimensional measurements.




Important: Use a 50-mm (2-in) stitch weld to avoid minimal heat distortion.

11. Using a MIG welder, weld completely around the sleeve joint.