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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Ben

42 years of experience
1589 reviews
Ben
42 years of experience
Dodge Charger V6-3.5L - Alternator - Houston, Texas
Ben changed the alternator on my 2010 Dodge Charger today with excellent customer service and ease. He arrived right on time and spared no wait to get started on my car. He was done with the repair after about 45 minutes and did his due diligence to make sure the alternator was charging properly. Will definitely be using this service again and will be requesting Ben!
Ford Focus - Alternator - Houston, Texas
Ben was Awesome!!! He was professional and courteous and had a wealth of experience and knowledge about cars. A real life saver!

Walter

47 years of experience
416 reviews
Walter
47 years of experience
Cadillac Eldorado V8-4.6L - Alternator - Tulsa, Oklahoma
Walter is literally the best mechanic I’ve ever come across. He went to great lengths and waaaay above call on my car. I got a bunch of his “Your Mechanic” cards, and recommended him to three people already. As long as I am in Tulsa, I will use Walter on all future repairs and maintenance for my 1995 Cadillac Eldorado! Thank you, Walter!
Honda Odyssey - Alternator - Sapulpa, Oklahoma
Very knowledgeable, patient, and great advice. Completed the task in a timely manner. Would recommend again.

Keven

8 years of experience
187 reviews
Keven
8 years of experience
Jeep Liberty V6-3.7L - Alternator - Tacoma, Washington
Very polite and speedy service. Even though the appointment was delayed by 2 hours, he was so quick that it made up the difference! Thank you!
Mazda 5 - Alternator - Puyallup, Washington
Kevin came early and he fixed my battery light issue! He was super fast and he did amazing with explaining what could have been the issue. As a single mom of 3, he took so much stress off my shoulders today!

Jose

21 years of experience
168 reviews
Jose
21 years of experience
Dodge Grand Caravan V6-3.6L - Alternator - Miami, Florida
Jose was very attentive, patient and methodical. My impression of Jose is that he knows the value of having loyal clients that keep coming back for the quality work and honesty. So he is upfront and frank about what needs to be done.
Dodge Ram 1500 - Alternator - Miami, Florida
Extremely knowledgeable! Very professional an courteous and takes the time to explain things! Excellent mechanic!!!!

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