How Long Does an Alternator Last (Every Factor Explained)

How long does an alternator last? Did your alternator go bad so quickly?

As a car owner or driver, when you consider your car’s electric power, what comes to mind is its battery. Although, the battery produces the smallest amount of power in a car.

The alternator is in control of giving power to your car’s features and electrical accessories such as the air conditioner, radio, lights, etc.

The function of a battery is to produce electrical charge and make ignition possible when you turn on the car. Another function is electrical reserve if the power flow of your alternator becomes faulty.

A car’s alternator can last between 80,000 to 150,000 miles, equivalent to seven to ten years.

However, there are other factors that will affect how long it will last. We will go through them in this guide, as well as signs of a faulty alternator, ways of maintaining an alternator, and every other information regarding the alternator. 

Let’s get started!

Car batteries do not last very long as alternators. The life expectancy of an alternator is between seven to ten years, depending on the model, make, and the length of miles you have driven the car.

Most vehicle owners expect between 80,000 miles to 150,000 miles on the alternator. Cars like Lexus, Toyota, and Honda will be on the range’s better, unlike economy vehicles or older ones.

You should know that it is not typical for your alternator to last as long as the car’s lifespan.

Factors That Affect the Lifespan of your Alternator

The function of an alternator is to supply power to a car’s battery and keep the electrical devices and system running. Unfortunately, things like using your radio, starting a car, heated seats, on-board navigation system, etc., decrease the lifespan of an alternator.

The action that generates electricity in the alternator is the rotor spinning past coils. But, first, it is spun on the needle bearing, which breaks from excessive dirt or wears and grime.

Also, the diodes found in a voltage regulator can become faulty. The car’s longevity can lessen because of heat on the engine, which causes a strain on some parts.

Therefore, the alternator does not last for eternity. How long it lasts depends on how you use the car, the engine conditions, the amount of electrical equipment used, etc. For example, some cars may keep operating properly after 100,000 miles, whereas others may become faulty at 40,000 miles.

On the alternator’s way out, it loses power to some of the electrical components when the car is idle. This happens because nothing is recharging the battery. A car cannot last with a failing alternator. You should get the car to the nearest trusted repair shop. Repair shops have vehicle information to determine what is wrong with the car.

Next, we will discuss the maintenance of an alternator and ways to prevent the breakdown of a battery or alternator by regulating its health.

Also Read: Transmission Slipping (Causes & Fix)

Why an Alternator Can Fail

An alternator might seem indestructible because it is made for dependability and longevity. Some alternators last as long as the said lifespan. Although some parts might wear down, and sudden failure might occur. Other problems are that it becomes totally out of commission, sporadic, or generates less electric power/energy.

  • Worn brushes cause a reduction in the alternator’s conductivity which can be a source of other alternator problems.
  • Output reduction from corroded or failed sections/parts of the car’s rotor might mean that the alternator needs to be repaired.
  • Underproduction or overproduction of electrical energy might mean that the regulator has a problem.
  • Broken or corroded electrical connections in the alternator can disrupt the current flow.

Most times, failure regarding an alternator can be from wear or over the tightened belt, which begins from a weird noise that leads to a catastrophic failure if not attended to.

Signs of a Bad Alternator

Battery Light

Depending on the model of your car, if your alternator starts failing, it lightens up several lights. However, the “ALT” or “Check Engine” indicator or red battery icon light remain on.

Lights Become Dim

A driver or car owner usually recognizes a flickering or dim light. It can be clearly seen at night and in the center dome light and dashboards. When the light brightens as RPMs pickup, it is a certain sign.

Electrical Issues

Windows or power seats may be sluggish to operate. In addition, when there is little power, some electrical devices may not function well or stop abruptly.

Odd Noises

Lack of charge and aging can make your alternator pulley not spin effectively, leading to a squealing sound. Grinding or growling noise can be from worn-out internal bearings.

Dead or Poor Battery

If the alternator is not functioning properly, the battery easily drains up. Examine the battery but know that a new battery with a failed alternator will leave you with problems again. These are things that you can do:

How Long Does an Alternator Last

How to Sustain Your Alternator

To maintain your alternator, always look out for red flags. Here are some steps you can take to prevent alternator hazards and maintain its functionality:

  • Learn the right method of jump-starting your vehicle.
  • Be cautious of the high-tech add-ons to your car because some aftermarket electronics or devices can negatively affect the alternator.
  • Check out for leakage in the alternator
  • Whenever you see the signs/symptoms of a faulty battery, fix the problem immediately. The problem may not be the battery but the alternator.
  • If your alternator needs to be changed, try to buy a new one.

When you keep up with these tips, your alternator can last long. However, note that even an alternator that has been properly cared for can have problems. Try to make your mechanic carry out a routine examination on your car.

How To Check Your Alternator

Check the battery, then your serpentine belt, analyze your alternator pulley, then finally check your serpentine belt tensioner. You can further inspect the alternator by using the multimeter to test the voltage of your battery. For the running engine, it will be from 13.5 – 15 volts. Ensure it remains so even as you revving the engine.

Also Read: Brake Pad Replacement Cost

Frequently Asked Questions – How Long Does an Alternator Last

What is the average lifespan of a car alternator?

It is between seven to ten years or 80,000-150,000 miles.

What causes an alternator to go bad?

Installing an electrical device that causes overload or when you jump-start a car wrongly. Also, a tight belt or leaking fluid can damage your alternator bearings and result in wearing.

How long does it take for an alternator to go bad?

Seven to ten years or 10,000 – 150,000 miles. Although some mechanics say it is 80,000 miles, some alternators can fail as early as 50,000 miles.

How much does a new alternator cost?

It costs from $400 to $600 to change the faulty alternator(with parts) and labor. So depending on your car, you will spend between $500 – $1,000 to purchase a new alternator.

Do alternators fail suddenly?

Yes, it can slowly or suddenly fail. This may lead to a breakdown.

Is it worth replacing the alternator?

When an alternator is malfunctioning, it is better to change it entirely. New ones are expensive, but you can use rebuilt or remanufactured ones. However, remember that it will not last like the new ones.

How often should the alternator be replaced?

If you are driving your car hard in Bradenton or Venice, you should change your alternator soon when it has lasted between seven to ten years.

Do you have to replace the battery when replacing the alternator?

When you install a new alternator, examine your battery and ensure that it is reconnected following the installation guide.

Conclusion – How Long Does an Alternator Last

Be particular about the age of your alternator and battery and the car’s mileage. Hence you can notice when the battery or alternator becomes faulty.

Note that going to a repair shop you do not trust is not a good option because they may not use a new alternator and still tell you it is new.

Therefore the said alternator(used one) will last between 2-4 years as opposed to 5-8 years. So ensure that you go to a trusted shop.

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