The alternator on a Ford Ranger is a small electrical generator mounted to the engine. Powered via a drive belt connected to the crankshaft, the alternator powers all of the electrical accessories on your vehicle, such as the stereo, headlights and windshield wipers. The alternator is also responsible for keeping the battery fully charged, so that your vehicle will start easily. If you're having trouble starting your Ford Ranger, or you notice the headlights are dim, it may be time to replace your alternator.
Open the hood.
Disconnect the ground cable from the negative battery terminal. Loosen the retaining bolt, using a wrench. Then pull the clamp off the terminal.
Loosen, but do not remove the bolts that connect the alternator to the engine bracket, using a socket.
Slide the alternator towards the engine.
Pull the drive belt off the pulley.
Label and disconnect the electrical leads on the back of the alternator, using masking tape and a marker.
Unscrew the bolts that attach the alternator to the engine bracket, using a socket.
Carefully lift the alternator away from the engine.
Lower the alternator into position in the engine bracket.
Screw in the bolts that connect the alternator to the engine bracket. Do not tighten.
Connect the engine wiring harness to the alternator, by pushing the plastic electrical connectors into the back of the alternator.
Slide the drive belt onto the alternator pulley.
Slide the alternator away from the engine until the drive belt is tight.
Tighten the mounting bolts, using a socket.
Connect the ground cable to the negative battery terminal. Slide the clamp over the terminal. Then tighten the retaining bolt using a wrench.
