Best Alternators: Boost Your Electrical Power and Performance
If you’re experiencing electrical problems, a worn or malfunctioning alternator may be the cause
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PUBLISHED ON November 13, 2019
Next to the battery, the alternator is the second most important component in your vehicle’s electrical system. While the battery provides power and stability, the alternator resupplies electricity to the battery. You can tell when your alternator is worn or broken because of the lights dim and components like electric windows and doors work slowly or not at all. When this happens, it’s time to purchase a new one. Choose one from our top picks below.
- Best OverallDB Electrical ADR0368 AlternatorSummarySummary
Our best pick fits on 2005-2007 Chevrolet and GMC trucks with 4.3L, 4.8L, 5.3L, 6.0L, and 8.1L engines. It has an amperage rating of 145 A.ProsPros
Easy and fast to install. It can take just 15 minutes to remove the old unit and install the new DB alternator. Performance curve and final test results supplied with some units. It’s an excellent value at an affordable price.ConsCons
It may fail within a few months after installation, and there have been some reports of poor quality control.
- Best ValuePremier Gear PG-13671 AlternatorSummarySummary
Our best value choice uses premium components, including brushes that resist failure and provide superior service. Fits Toyota trucks, including the 4Runner and Tacoma. It’s a 12-volt, 70 amp unit.ProsPros
This alternator has a Denso, internally regulated fan. The alternator offers protection against shorts that may occur in your vehicle’s wiring. Manufacturing processes exceed OEM specs for wiring and bearings, which delivers exceptional moisture and heat resistance.ConsCons
It may be difficult to install on a Toyota 4Runner. Also, the internal voltage regulator may fail.
- Honorable MentionParts Player F- Series AlternatorSummarySummary
This economically-priced alternator fits most late 1990 and early 2000 Ford F-series trucks and some GM trucks. It is manufactured with new premium-quality components that meet or exceed OEM specs. The amperage rating is 130 A.ProsPros
The manufacturer tests all units for performance, reliability, and durability before shipping. The unit is easy and quick to install. Some units actually exceed the amp rating, putting out around 145 amps versus 130.ConsCons
Some units may have a bad voltage regulator or put out too much voltage, 17.7 volts, while it should be around 14.
Why Trust Us
All of our reviews are based on market research, expert input, and practical experience with each product we include. This way, we offer genuine, accurate guides to help you find the best picks.
- Signs of a faulty alternator are dim lights, including headlights, taillights, brake lights, and dashboard lights; low blower output; problems with the radio or sound system; and slow or nonexistent electric window and door lock operation.
- Test your alternator with a multimeter for voltage and amp output to see if it is generating power as it should before you replace it.
- The alternator is an important part of your vehicle’s electrical system, but it is only one part. Many factors affect the system’s operation. If you have doubts about whether your alternator is faulty, have it professionally tested before you replace it.
Q: How do I know which alternator is right for my vehicle?
A: Check the product’s details. If you have a part number from the unit that is in your vehicle, you can check it against the numbers in the product’s list. You can also compare amperage, voltage, and mounting requirements. Read recommendations in customer reviews too.
Q: Which is better: a new alternator or a rebuilt one?
A: There’s no clear answer. Some rebuilders use better parts to rebuild an alternator than OEMs use on new ones. Others test more thoroughly one way or another. Check the specifications and reviews, weigh the pros and cons, and then make your own determination.
Q: When my alternator warning light goes on, do I have to replace the alternator?
A: Not necessarily. If the light turns on and then goes off again, it means the onboard computer checked your system, including your alternator, and determined nothing is wrong. If the light remains on, it means the computer has determined there is an issue with your electrical system, but the problem may not be limited to the alternator. Test it before you replace it.