Service Procedure
NOTEPERFORM THE FOLLOWING PROCEDURES AS NECESSARY TO REPAIR CRACKS AND REINFORCE ONE OR BOTH SIDES OF THE FRAME. IT SHOULD BE NOTED THAT IF THE VEHICLE IS SUBJECTED TO A HIGH STRESS EVENT AGAIN, NEW CRACKS MIGHT APPEAR IN THAT AREA.
CAUTION
ALWAYS DISCONNECT THE BATTERY GROUND CABLE PER WORKSHOP MANUAL SECTION 414-01 BEFORE USING ANY ELECTRICAL WELDING EQUIPMENT. USE ONLY MIG ER-70-56 WIRE WHEN WELDING.
REAR FRAME AND BODY SPLIT
NOTE
DO NOT PERFORM THIS PROCEDURE IF THERE IS NO CRACK ON THE TOP SURFACE OF THE FRAME.
In this procedure the bumper cover will be loosened to prevent damage to the cover when the body of the vehicle is lifted away from the vehicle frame. The frame will be split from the body to provide clearance necessary to repair cracks on the top of the vehicle frame.
1. Position the vehicle on a hoist making sure there is adequate access to the body mount bolts (Figure 4) and the lower trailing arm flag nut access hole (see Workshop Manual Section 100-02).
2. Open the hood and disconnect the battery per Workshop Manual Section 414-01.
3. Open the trunk.
4. Remove/place aside the trunk trim on the sides and remove the four (4) rear bumper cover nuts in the trunk (two (2) on each side) (Figure 5 shows left hand side).
NOTE
IT IS NOT NECESSARY TO REMOVE THE LUGGAGE COMPARTMENT REAR TRIM PANEL.
5. Raise the vehicle to chest height.
6. Remove the rear wheels.
7. Remove the rear bumper cover screws from under the bumper fascia rear lip (two (2) or three (3) screws), (Figure 6) and the push pin type retainers from bottom sides of bumper cover (two (2) or three (3) on each side) (Figure 7), six (6) push pin-type retainers (three (3) on each side) in the wheel well at the leading edge of the bumper (Figure 8).
8. Remove the # 2, 3, 4, 5, and 6 body mount bolts on both sides. Refer to (Figure 4) for locations of body mount bolts.
NOTE
THE # 4 BODY MOUNT BOLTS ARE NEAR THE SPRING SEAT.
9. Install a 2X6 block of wood and two (2) jackscrews up tight against the body between the body drain plugs, partially under the trunk and the fuel tank (Figure 9).
10. It present, unclip the ground strap from the # 6 body holes on the frame on the right and left hand sides. The ground straps are located between the # 6 body hole and the rear cross member.
NOTE
DURING STEP 11, WATCH THE BUMPER COVER TO MAKE SURE IT DOES NOT HANG UP ON THE BUMPER REINFORCEMENT BAR. IF IT HANGS UP, THE BUMPER COVER MAY BE DAMAGED.
11. With the jackscrews and wood supporting the weight of the rear of the body, SLOWLY lower the lift so that the body splits from the frame. It will be necessary to create about a 12.7 cm (5") air gap between the frame and the body, at the # 5 body mounts location. Insert a 11.5 to 12.7 mm (4.5" to 5") tall block of 4X4 wood between the frame and the body mounts at the # 5 body mount location on both sides of the vehicle. The block will be flush to the cage nut reinforcement (Figure 10).
12. Raise the hoist and remove the jackscrews.
REPAIR OF FRAME CRACKS BETWEEN THE UPPER AND LOWER TRAILING ARM MOUNTING BRACKETS
NOTE
REFER TO (FIGURES 1 AND 2) FOR THE TYPICAL LOCATION OF THE CRACKS. DO NOT PERFORM THIS PROCEDURE IF CRACKS ARE NOT PRESENT ON THE SIDE RAIL BETWEEN THE UPPER AND LOWER TRAILING ARM BRACKETS.
NOTE
PERFORM THIS REPAIR ON BOTH SIDES OF THE FRAME IF NECESSARY.
1. If necessary, bend the spot-welded flange at the bottom edge of the inner fender well for improved access~to the frame crack (Figure 11).
2. On the left side only, remove the brake line clip and reposition the line away from welding area.
3. Use an angle grinder to clean off paint and dress the weld area.
4. Weld crack as necessary.
5. Brush on Motorcraft PM-12-A Low Temperature Anti-Corrosion Coating to all weld repair areas.
6. Replace the brake line.
7. Re-bend weld flange into place.
LOWER TRAILING ARM MOUNTING NUT ACCESS HOLE OPENING REPAIR AND/OR REINFORCEMENT
In this procedure any cracks in the frame area around the lower trailing arm flag nut access hole opening will be repaired. A metal blocker baffle (4W73-4A145-AA) will be inserted into the side rail, and a reinforcement plate (4W73-5A123-AA or 4W73-5A124-M) will be welded to the bottom rail of the frame to close the access hole to strengthen that section hole.
NOTE
THE BLOCKER BAFFLE WILL PREVENT LEAKAGE OF THE STRUCTURAL FOAM, WHICH WILL BE INTRODUCED INTO THE FRAME.
1. Partially raise the vehicle and locate the access hole for the lower trailing arm. This access hole is located on the bottom of the frame, directly under the lower trailing arm mounting bracket. Inspect for cracks at the lower trailing arm access hole (Figure 3). If cracks are present repair them as necessary.
2. Use an angle grinder to clean off paint and dress the weld area.
3. Weld crack as necessary.
4. Bend two (2) metal Blocker Baffles (one (1) for each side) (4W73-5A145-M) along the crease on the middle of the part.
5. Insert the baffle into the access hole with the narrow end facing upwards. Minimize bending the flanges. The blocker baffle will prevent the structural foam from running out of the frame and/or covering the trailing arm nut. The flanges should face the front of the car (Figure 12).
6. Once inside the rail section, unbend and position the blocker baffle to get a tight seal to the frame rail section. Perform one of the following procedures:
a. On the left hand side bracket, line up the bottom edge of the blocker baffle flange to the rear edge of the access hole. The top end of the baffle must be 6 to 12 mm (1/4" to 1/2") forward of the top rear weld on the lower trailing arm bracket. Inspect the blocker baffle for a good seal between the frame and the blocker baffle. If needed, using a flat screwdriver push all the flanges of the blocker baffle to improve seal between the blocker baffle and the frame. The flag nut may need to be bent out of the way to accommodate the blocker baffle. Tack weld the blocker baffle.
b. On the right hand side bracket, line up the vertical face of the blocker baffle to the rear edge of the access hole. The top end of the baffle must be 6 to 12 mm (1/4" to 1/2") forward of the top rear weld on the lower trailing arm bracket (Figure 12). Inspect the blocker baffle for a good seal between the frame and the blocker baffle. If needed, using a flat screwdriver push all the flanges of the blocker baffle to improve seal between the blocker baffle and the frame. Tack weld the blocker baffle.
7. Grind the area around the access hole in the bottom of the frame at the trailing arm, including any welds that may have been added to repair cracks. Grind any welds where needed for proper location of the reinforcement patch (Figure 13). Do not grind away the parent metal. The reinforcement plate must be located flush to the frame.
8. Center the slot of Reinforcement Patch (4W73-5A123-AA right hand side marked "R") or 4W73-5A124-M left hand side (marked "L") to the center of the trailing arm bolt taking care that the frame rail does not overlap the slot (Figure 14). Tack in place, then weld around the reinforcement plate completely (Figure 15 and 16).
REINFORCE FRAME WITH STRUCTURAL FOAM
In this procedure the frame rail section will be reinforced with Motorcraft Structural Foam that will add strength to the frame and reduce the potential for cracks in the frame in the area.
1. Clean around the tooling hole and all other holes in the area on the frame rail located between the upper and lower trailing arm-mounting brackets (Figure 17 and 18).
2. Apply duct tape over the holes.
3. Pierce a 6 mm (1/4") hole into the duct tape covering the outer tooling hole to allow easy introduction of the nozzle into the tooling hole through the tape (Figure 19).
4. Lower the vehicle to chest height.
NOTE
IT IS SUGGESTED THAT GLOVES BE WORN WHEN WORKING THE HEATED TUBES OF MOTORCRAFT STRUCTURAL FOAM AS OUTLINED IN STEPS 5 THROUGH 7. ADDITIONALLY, THE STRUCTURAL FOAM WILL CAUSE THE SIDE MEMBER SURFACE TO BECOME VERY WARM AS A RESULT OF THE CHEMICAL REACTION.
5. Put the five (5) tubes of 1U2J-19554-DA Motorcraft Structural Foam on a table and heat the tubes front and back with a heat gun to approximately 71.1 °C (160 °F). This will help soften the two parts of the Structural Foam so that it will flow out of the tubes and through the mixing wand easily (Figure 20).
6. Remove the small black plugs from a tube of structural foam. Install the nozzle (4W73-19H255-M) and replace the holding nuts. Balance the plungers by gunning out some material. Ensure that it comes out from both tubes. Press the tab on the back of the gun to relieve pressure. This will prevent the foam from streaming out of the tube uncontrollably.
7. Insert the nozzle through the hole cut into the duct tape in the outside tooling hole (Figure 19). Pump the tube of Structural Foam into the frame rail. When the Structural Foam rises to the height of the tooling hole, it will be necessary to duct tape the hole when switching tubes to prevent leakage of the Structural Foam.
NOTE
REPEAT STEPS 6-7 UNTIL ALL FIVE (5) TUBES OF 1U2J-19554-DA MOTORCRAFT STRUCTURAL FOAM HAVE BEEN PUMPED INTO THE FRAME. ALLOW AT LEAST THIRTY (30) MINUTES FOR THE STRUCTURAL FOAM TO CURE BEFORE REMOVING THE DUCT TAPE.
8. Raise the vehicle all the way up.
9. Remove duct tape.
10. Brush on Motorcraft PM-12-A Low Temperature Anti-Corrosion Coating to the weld areas.
REASSEMBLE FRAME AND BODY
In the following steps the frame will be reassembled to the body, and the bumper fascia will be reinstalled.
NOTE
REQUIRED ONLY IF THE "REAR FRAME AND BODY SPLIT" PROCEDURE WAS PERFORMED.
1. Partially raise the vehicle.
2. Reinstall a 2X6 block of wood and two (2) jackscrews up tight against the body between the body drain plugs, partially under the trunk and the fuel tank (Figure 9).
3. Lower the hoist until the 2X6 block fits snug against the body.
4. Remove the wood block between the frame and the body mounts at the # 5 body mount location on each side of the vehicle (Figure 10). It may be necessary to further lower the hoist by 6 to 12 mm (1/4" to 1/2").
5. SLOWLY raise the hoist until the frame is off the jackscrews and is flush with the body. Watch the bumper cover to make sure that it does not become damaged.
6. Remove the jackscrews and the 2X6 block from under the vehicle.
7. Clip the ground strap to the #6 body holes on the frame on the right and left hand.
8. Reinstall the # 2, 3, 4, 5, and 6 body mount bolts on both sides.
9. Torque bolts to 48-50 N.m (35.4-36.8 lb-ft).
10. Partially lower the vehicle to waist height.
11. Relocate the bumper fascia and four (4) bumper cover nuts (two (2) on each side).
12. Torque bolts to 7 N.m (61.9 lb-in) (Figure 3 shows left hand side).
13. Reposition trunk trim sides.
14. Partially raise the vehicle.
15. Replace the six (6) pin-type retainers (three (3) on each side) in the wheel well leading edge of the bumper (Figure 8) and the push pin-type retainers (two (2) or three (3) on each side) from bottom sides of bumper cover (Figure 7).
16. Partially lower the vehicle.
17. Replace the rear wheel and tire assemblies.
18. Lower the hoist.
19. Close the trunk.
20. Reconnect the battery per Workshop Manual: Section 414-01.
21. Close the hood.