Attachment III - Technical Instructions
SUBFRAME REAR LOWER BODY
MOUNT REINFORCEMENT INSTALLATION
TECHNICAL INSTRUCTIONS
1. Raise vehicle on hoist. Refer to the 1988 Car/Truck Service Manual, Volume F, Section 50-04.
2. Support both engine/transmission subframe members at the rear body mount locations with adjustable jacks. Refer to Figure 1.
3. Locate two (2) holes in the body floor pan. Both holes are slightly behind the subframe near lower body mounts - one located outboard and one located inboard of each rear mount position.
4. Through these two holes at each rear mount, liberally coat or spray the upper bolt threads and plate nut with Rust Penetrant (Part Number F2AZ-19A501-A or equivalent). Wait for 3 to 4 minutes then forcibly tap the head of bolt with a brass hammer.
5. Using hand wrench and socket, slowly apply force to loosen the bolt.
NOTE 1:
DO NOT USE AN IMPACT WRENCH. THIS CAN CAUSE STRIPPING OF THREADS OR CAN BREAK THE PLATE NUT LOOSE FROM ITS RETENTION. THIS WILL CAUSE EXTENSIVE ADDITIONAL REPAIRS.
NOTE 2:
IF THE BOLT CANNOT BE REMOVED (continues to spin), REFER TO "PLATE NUT REPLACEMENT" PROCEDURE OUTLINED ON SHEET 3 AND 4 OF THIS INSTRUCTION SHEET.
6. DO NOT remove lower body mount.
7. Install the added reinforcement plate to the bottom of the existing lower mount and install the new retaining bolts. Torque to 75-102 N-m (56-75 lb.ft.). Be sure to install the reinforcement plate with the shouldered area toward the mount.
8. Remove adjustable jacks. Lower and release vehicle.
PLATE NUT REPLACEMENT (Refer Figure 2 and 3)
* * * ATTENTION * * *
USE THIS PROCEDURE ONLY IF THE BOLT CANNOT BE REMOVED (SPINS)
Use the following procedure to replace the plate nut at the subframe-to-body rear attachment location.
NOTE:
Before starting this procedure, make sure the subframe is supported at the locations shown in Figure 1.
1. From under the vehicle, cut the head off the subframe body mount bolt. Cut with a metal cutting saw just above the metal retainer of the lower absorber.
CAUTION:
Lower absorber is compressed and will expand once bolt head is cut through. Exercise care to avoid injury.
NOTE:
If both bolts spin ONLY work on one mount at a time.
2. Roll back the front carpet and pad in order to expose the drill dimple in the front floor pan located directly above the subframe attachment. It may be necessary to cut away a small portion of the sound deadener which is banded to the floor pan to clearly see the drill dimple. (See Figure 3).
3. Measure 2.5 inches directly below the drill dimple and center punch this new location. (See Figure 2).
4. Using a hole saw, drill a 2.5 inch hole in the floor pan at this new location. Remove and discard slug.
5. Through the drilled hole, bend existing plate nut tabs upright and remove nut and bolt.
6. Position new nut over tabs and bend tabs down to retain nut.
7. Apply Super Seal (Part Number D8AZ-19515-BA (CXC-L-B) or equivalent) to exposed metal of drilled hole. Install Plug Button (Part Number 385138-S) and replace carpet and pad.
8. Lower adjustable jacks at the rear body mount location just enough (approximately 2 inches) to provide room to remove the existing subframe rear upper body mount.
9. Remove the existing subframe rear upper body mount.
10. Install a new Rear Upper Body Mount, Part Number E6DZ-5400396-A (1988 Continental); or F1DZ-5400396-A (1986-88 Taurus/Sable) into the subframe from the top.
11. Raise adjustable jacks to position upper rear body mount/subframe to the vehicle body.
12. Install a new Rear Lower Body Mount, Part Number F3DZ-5400155-A.
13. Proceed to Step 7 of Sheet 1 of this Instruction Sheet.