How to Replace an Alternator on a 2003 F-150

The F-150 has become one of Ford Motor Company's most popular brands. It is most known for its unique style and performance. The 2003 model represented the last phase of what was widely considered the best body style. The most common motor size used in the F-150 is the V-8. To run a V-8 takes power. As you may already know, the alternator is used to charge the battery and to power a car's electrical system when its engine is running. The alternator you are replacing has a big job to do.

Things You'll Need

  • Automotive gloves
  • Safety glasses
  • Adjustable wrench
  • Purchase a new alternator from your local certified auto parts retailer. Request the original part made for the 2003 Ford F-150. Keep your receipt as it will come in handy to receive credit for your old alternator.

  • Disconnect completely the top post battery located on the right side of the truck. Unscrew the bolts that are holding the clamps on the posts with an adjustable wrench until they are loose. Pull the clamps off and let them hang to the side.

  • Remove the bolt at the top and the bottom of the alternator with your adjustable wrench. The alternator is on the opposite side of the car from the battery, all the way to your left, in the front and on the side of the motor. The bell will naturally begin to fall off the pulley wheel; pull the belt off completely. Unplug the red and white adapter that is connected to the motor.

  • Install the new alternator by positioning it the same way you found the old one before you unscrewed it. Place the belt back on to the pulley wheel. With an adjustable wrench, screw in the same two bolts that you removed in Step 3. Tighten these bolts as tightly as you possibly can, even using a little body weight. Plug the red and white plug back into the side of the motor.

  • Reconnect the battery one post at a time, tightening them both securely with an adjustable wrench.

  • Start the vehicle and listen for any unusual sounds, such as rattling. Test drive the truck.