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"04 3.8 Mustang killing battery..

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Old 09-21-2013, 08:23 PM   #1
Join Date: Sep 2013
Vehicle: 2004 LT
Location: NC
Posts: 1
Default "04 3.8 Mustang killing battery..

Hey guys,my brother has an 04 Mustang LT with a 3.8. He says in about 7 to 8 months it will kill the battery,any thoughts on this? He said the knucklehead at Autozone told him the diodes in the alternator were going out..Thoughts?..Thanks in advance..Phil

I don't have a stang,but I'm a Superduty diesel guy,still Ford brotherhood..right?..LOL
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Old 09-21-2013, 08:46 PM   #2
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Sounds right to me. Get the alt rebuilt. May need both diodes and brushes. Im surprised it lasts 7 months.

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Old 09-22-2013, 07:38 AM   #3
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Posts: 164

can you check the battery w/ a volt meter?

one w/ the car off (i think it should be low 12s)
one w/ the car running.(i think this should be mid 13s)

check if the battery also hold a charge to rule out if its the battery or the alternator.
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