REMOVAL OF STOCK TRAILING ARMS
1. Place car on level surface and place tire chocks in front of and behind front tires
2. Support rear of the car on jackstands and remove the rear wheels.
3. Lift rear axle with floor jack to approximate ride height, then support rear axle with jack stands (See Fig. 2).
KEEP JACKSTANDS UNDER CAR DURING THE COMPLETE REMOVAL AND INSTALLATION PROCEDURE. CAUTION – DO NOT REMOVE BOTH TRAILING ARMS AT THE SAME TIME OR THE AXLE WILL ROTATE AND TRAILING ARM INSTALLATION WILL BECOME MUCH MORE DIFFICULT.
4. Remove rear sway bar. Remove clip nuts from sway bar (See Fig. 3). Make sure car is still firmly supported on jackstands.
5. Lift rear of trailing arm with floor jack so bolt can be removed (See Fig. 4). Remember, do one side at a time.
6. Carefully remove rear trailing arm bolt. CAUTION: Trailing arm is under tremendous pressure from the rear spring. Be sure that the floor jack is sturdy and able to control the release of tension in a smooth, controlled manner.
7. Carefully lower trailing arm, releasing tension on rear spring. Note that the opening at the bottom coil of the spring is towards the rear of vehicle. It must be re-installed in the same position or the ride height will be affected. Remove spring. Inspect the rubber insulators on spring and replace with new Ford parts (#D8BZ-5536-A), if necessary.
8. Remove front bolt and old trailing arm. A 14″-16″ long extension will make it easier to reach the bolt due to interference from the muffler.

Installation:
1. Install bushing sleeve in bushing using supplied grease. Bushing sleeve with small hole is for model years 1979-1998 and sleeve with large hole is used for 1999–2004 model years.
2. Install new trailing arm with the grease fittings facing down and the sway bar mount toward the front of car. Arm stamped with P/N 25-4003 is the left and P/N 25-4004 is the right.
3. Install the new trailing arm by locating the front bolt first. If the fit is too tight, grease the outside edges of the bushing to help the arm slide into place. Install nut and bolt but do not tighten at this time. The trailing arm should pivot smoothly in the chassis.
4. Re-install spring and all rubber insulation pieces, making sure that opening at bottom of spring faces the rear of the car (See Fig. 5). Use a block of wood or similar support between the floor jack and the trailing arm to prevent damage to the zerk fitting (See Fig. 6).
5. Place one drop of blue Locktite™ on clean threads and torque the nut to 70 ft./lbs on both front and rear trailing arm bolts.
6. Repeat for other side.
7. Re-install sway bar with ends to outside of trailing arm sway bar mount. Use factory bolts with supplied nuts and washers. Re-install E-brake cable clamp on rear most sway bar bolt if equipped. Bracket may require minor modification.
8. You may want to finish your installation by lubing the front and rear bushings with a grease gun. Be sure to replace the dust caps on the zerk fittings to prevent dirt and corrosion from damaging the fitting.

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