How to Replace the Alternator in a Ford Mustang

by Contributor

The Ford Mustang has an alternator that sends electrical current to various devices in the vehicle while the engine is running. Most alternators made today include a voltage regulator that ensures the voltage level remains constant. You may need to replace the alternator if your battery keeps running down or your headlights become dimmer while driving.

Determine which alternator your Ford Mustang needs. Be sure the new alternator is compatible with your Mustang's engine. Models made from 1964 to 1973 come in a range of engine sizes, including 170 cubic inch (ci), 200 ci, 250 ci, 260 ci, 289 ci, 302 ci, 351 ci, 390 ci, 427 ci, 428 ci and 429 ci.

Examine later models of the Ford Mustang. Models built from 1974 to 1978 were restricted to 140 ci, 171 ci and 302 ci engines. Models manufactured from 1979 to 1993 were available in 2.3 L, 3.3 L, 3.8 L, 4.2 L and 5.0 L sizes. Models made from 1994 to 2004 may be equipped with a 3.8 L, 4.6 L, 4.9 L, 5.4 L or 5.8 L engine.

Look at the current generation of the Ford Mustang. Models made after 2005 have a 4.0 L Cologne, 4.6 L Modular or 5.4 L Triton supercharged engine.

Disconnect the negative battery cable with a socket wrench and remove the accessory drive belt. Unplug the electrical connector for the alternator. Remove the alternator shield if you have a 4.0 L engine and the air intake scoop bracket if you have a 4.6 L engine.

Take the mounting bolts off the alternator with a socket wrench and remove the alternator assembly.

Install the new alternator assembly onto the engine. Tighten the mounting bolts to 18 foot-lb. in most cases. However, if you have a 3.8 L or 4.0 L engine, you should torque the lower bolt to 35 foot-lb.

Connect the alternator shield if you have a 4.0 L engine and the air intake scoop bracket if you have a 4.6 L engine. Install the accessory drive belt and connect the negative battery cable with a socket wrench.

Items you will need

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