Should I repair or replace my alternator?

Anything can be repaired, but the question is whether it’s worth it to repair an older alternator. Say, for instance, the brushes on your current alternator are worn and no longer providing accurate current to the rotor. If you replace the brushes today and the alternator is running perfectly again, you may only get a few thousand miles out of it before you have to address issues with other parts, like the bearings. You also need to question whether your repair, or the work of a mechanic, will be as accurate as work done on a factory assembly line, with specialized tools and quality control. 

Even if you trust the workmanship of your mechanic, the time that it would take to repair an alternator would probably cost more than a new alternator, since prices for new units range from $200 to $400 for most models and many are cheaper than that. If, on the other hand, you’re doing the repair as a fun project, or just to see if you can do it, feel free to give it an attempt. If you want a lasting solution, though, your best bet is probably to replace the alternator with a new or remanufactured unit. 

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Be sure to consult your owner’s manual, a repair guide, an AutoZoner at a store near you, or a licensed, professional mechanic for vehicle-specific repair information. Refer to the service manual for specific diagnostic, repair and tool information for your particular vehicle. Always chock your wheels prior to lifting a vehicle. Always disconnect the negative battery cable before servicing an electrical application on the vehicle to protect its electrical circuits in the event that a wire is accidentally pierced or grounded. Use caution when working with automotive batteries. Sulfuric acid is caustic and can burn clothing and skin or cause blindness. Always wear gloves and safety glasses and other personal protection equipment, and work in a well-ventilated area. Should electrolyte get on your body or clothing, neutralize it immediately with a solution of baking soda and water. Do not wear ties or loose clothing when working on your vehicle.

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