Q: A new battery will not hold charge overnight. alternator is not the problem / 2 mechanics checked.

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I have a new battery that will not hold a charge overnight. The alternator is not the problem and it was checked by 2 mechanics. The battery continues to drain overnight and needs a jump start everyday. could it be the wrong battery?

My car has 145000 miles.
My car has an automatic transmission.

Hello. If the battery continues to drain overnight despite recent replacement, then there might be some sort of electrical short or malfunction somewhere on the vehicle that is draining the battery. A good battery should hold a charge overnight without any issue. A simple load test should be able to determine if the battery is good or not.

There is also the possibility that you may have the incorrect battery. Your vehicle uses a 4.6L V8, and has a considerable amount of electronic accessories, and will experience all sorts of issues if the incorrect battery is used. I would verify that the battery is the correct size, and able to hold a charge, and then move on to examining the possibility of an electrical short. If you need further assistance with this, a certified technician from YourMechanic can inspect the battery firsthand to pinpoint the problem and make appropriate repairs.

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