How Long Does an Alternator Last?

Your alternator is a vital component in your car. It recharges your battery, using engine power, and it also delivers power to your car’s electrical components. Essentially, it keeps the battery from losing charge, and of course if your battery dies, your car is simply not going to work.

You ask a lot of your alternator these days. In times gone by, it didn’t have to do much more than just power your headlights, and a few accessories like your radio. But think about all the accessories your car comes with today – entertainment systems, for instance, use up a lot of power, and then you probably also have on-board navigation, power windows, power mirrors, and perhaps even heated seats. All these “extras” need to receive power from your alternator. So, your alternator works every day, from the moment you start up your car until you turn it off. And if your alternator is failing, you will need to replace it.

Many factors can affect the life of your alternator, so it is difficult to say how long you can expect it to last. It will not usually last the life of your car, though. For one thing, the alternator’s rotor spins on a needle bearing, and this is a component that can break due to wear, or a buildup of dirt. The diodes in the voltage regulator can also fail, and engine heat puts strain on the alternator. Generally speaking, you can expect your car alternator to last anywhere between 40,000 and 100,000 miles.

Signs that your alternator is wearing out include:

  • Loss of power to various accessories when your car is idling
  • Dimming headlights
  • Dimming dashboard lights
  • ALT or GEN light is on

If you notice any of these symptoms, you should have your alternator checked. A professional mechanic can diagnose the problem with your alternator, and replace it if necessary.


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Attila

19 years of experience
906 reviews
Attila
19 years of experience
Infiniti G37 V6-3.7L - Alternator - Basking Ridge, New Jersey
He was faced with a difficult situation due to unexpected rusted bolts, poor access, etc. but he got the job done on time and on budget.
Honda Accord - Alternator - Scotch Plains, New Jersey
Mr. Paniti was punctual and very professional. He kept me up to date on what was going on. He had to go pick up the right alternator, he called me and informed me of the situation. The car started and he made some recommendations. Great service Thanks

Collins

12 years of experience
488 reviews
Collins
12 years of experience
Acura RL V6-3.5L - Alternator Repair - Atlanta, Georgia
Collins is a true professional. Arrived on time and answered all of my questions. I would use him again.
Nissan Altima - Alternator - Atlanta, Georgia
Collins was incredibly kind, professional, and went above and beyond to get my car running. So thankful to God of all the mechanics that I was blessed with him. ❤️❤️❤️ Thank you 

Thomas

12 years of experience
96 reviews
Thomas
12 years of experience
Jeep Patriot L4-2.4L - Alternator Repair - Grand Prairie, Texas
First time using your mechanic app and Thomas was great! Attentive, kind, and professional. Made sure everything was good to go before leaving.
Honda Civic - Alternator - Fort Worth, Texas
Thomas was very knowledgeable in both mechanical and electrical issues with my car. He was great with explanation of the issue, as well as making the repairs to my car efficiently. I highly recommend him as a mobile mechanic to anyone I know!

Robert

20 years of experience
1089 reviews
Robert
20 years of experience
Mercedes-Benz C300 V6-3.0L - Alternator - Thornton, Colorado
Was on time and completed the job to my satisfaction. Will use again when any of my cars or trucks needs work done to them. Thank you.
Toyota FJ Cruiser - Alternator - Westminster, Colorado
Robert is a great mechanic, and I will definitely be looking to use him for further work. I used to troubleshoot and work on cars, but I lack the expertise to tackle modern electrical systems. Robert efficiently diagnosed the problem, and fixed the car within the estimated timeframe.

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