The Ford Motor Co. used a rear anti-lock brake system on the 2001 F-150 trucks. Information gathered by the ABS sensor is relayed to the ABS brake module. The module controls the actual braking force applied to the rear wheel through the brake fluid isolation system and dump solenoid to prevent rear wheel lockup. Electrical pulses, generated by the teeth on the ABS gear in the rear differential as they pass by the ABS sensor, indicate the rotation speed of the rear wheel. Damage or wear on the ABS sensor can cause improper or reduced functionality of the ABS system, which can lead to a dangerous driving condition.
Chock the front wheels.
Place a jack under the rear jacking point on one side of the rear axle between the axle U-bolts. Jack up the vehicle to obtain sufficient clearance to access the rear differential. Place a jack stand on the jacking point and next to the jack for safety.
Locate the ABS sensor on top of the rear differential. Clean accumulated dirt and debris from around the ABS sensor with a shop rag.
Unplug the ABS sensor electrical connector. Remove the sensor retaining bolt using a ratchet and socket. Pull the ABS sensor out of the rear differential. Wipe the mounting surface clean with a shop rag.
Lubricate the new ABS sensor O-ring with SAE 75W-140 lubricant. Insert the new sensor into the rear differential. Install the retaining bolt and tighten it to 20 foot-pounds of torque, using a foot-pound torque wrench and socket.
Plug the ABS sensor connector into the sensor.
Remove the jack stand. Lower the jack until the vehicle is back on the ground. Remove the jack and the front wheel chocks.
