Standard Procedure - Rear Frame Rail Replacement: Notes

Fig 1: Rear Frame Rail Replacement Components

Courtesy of CHRYSLER GROUP, LLC

"Rail, rear, outer" (2) - this portion of the rear rail assembly is not visible as it is gloved inside the "rail, rear, inner" (3) and the "cover plate, rear rail extension" (1). This rail may not be sectioned! 

"Reinforcement, rear rail inner rear" (4) - welded inside of the "rail, rear, inner" (3) and extends from the end of that rail to the "panel, deck opening lower".

Fig 2: Rear Inner Rail

Courtesy of CHRYSLER GROUP, LLC

"Rail, rear inner" may be sectioned at this location (1), greatly reducing vehicle disruption and repair costs.

This partial replacement procedure presumes that all damage to the "rail, rear inner" is aft of the crossmember (2).

Left side 

Fig 3: Left Rear Rail Cut Locations

Courtesy of CHRYSLER GROUP, LLC

The "Reinforcement, Rear Rail Inner, Rear" (3) ends 100 mm (4 in.) (2) forward of round hole (1) on inner face of "Rail, Rear Inner" - recommended cut location is 125 mm (5 in.) (4) from forward edge of the hole (1).

Right Side 

Fig 4: Right Rear Rail Cut Locations

Courtesy of CHRYSLER GROUP, LLC

The "Reinforcement, Rear Rail Inner Rear" (4) ends 125 mm (5 in.) (1) forward of round hole (2) on inner face of "rail, rear inner" - recommended cut location (3) is 150 mm (6 in.) from forward edge of hole (2).

The following procedure details key points of the repair. I-CAR training is presumed, and should be followed for best-practice repair procedures. 

1. Mount the damaged vehicle onto a structural straightening bench and check/correct any body misalignment utilizing three dimensional measuring equipment.
2. Remove all components in area of repair allowing unimpeded access for cutting and welding operations.
3. Trunk floor should be removed if being replaced, or the necessary welds released and the weld flange bent inboard to provide access to the rail for the butt-joint.
4. Using the round hole in the "Rail, Rear, Inner" as a point of reference, measure 125 mm (5 in.) forward for the left rail, or 150 mm (6 in.) forward for the right rail, and scribe a vertical line on the rail.
5. With the vertical line just made as reference, cut off the damaged "Rail, Rear, Inner" taking care not to damage the "Rail, Rear, Outer", using a reciprocating saw or cut-off wheel, and remove the damaged portion.
6. Utilize the same measuring and cutting process above to remove the replacement portion from the service part.
7. Using a surface conditioning disk, remove all e-coat within 25 mm (1 in.) of the cut location and de-bur the cut edge.
8. If the "Rail, Rear, Outer" was damaged during the cutting operation, MIG-weld the damage and dress the weld.
9. Fabricate 19 mm (0.75 in.) weld backers from the damaged component, or the remains of the service part, and tack in place on the replacement rail section at the butt-joint location.
10. Position and clamp the replacement rail and confirm proper position with measuring equipment.
11. Weld the service part in position using a skip-stitch process.
12. Complete remaining repairs in the damaged area.
13. Clean and dress all welded areas.
14. Apply epoxy primer to the exterior of the rail at the repair location.
15. Apply quality body sealer to all areas previously sealed to duplicate the original appearance. Note that additional sealer may be applied to better protect the exterior exposed seams from road spray.
16. Refinish all exposed surfaces in trunk and on underbody using quality refinish materials.
17. Apply inner panel rust proofing, such as Mopar # 05093981AA, or equivalent, to the rail inner cavity areas in two applications with a 30-minute flash period between the applications. Pay particular attention to areas which have been welded.
18. Reassemble vehicle and complete repairs.