How often do alternators need to be replaced?

In general, you can expect alternators to last about 6-10 years, or about 80,000-150,000 miles.

Can a bad alternator ruin a new battery?

Can a bad alternator kill a new battery? Yes, very easily. A failing alternator can overcharge, which will damage the battery. An undercharging alternator will leave the battery flat, which speeds up its failure.

Can an alternator go bad in a year?

If you're noticing that your car is having problems starting, you may be wondering just how often do alternators go bad? Alternators can typically last a long time, about seven years or 100,000 to 150,000 miles.

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