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So my battery light came on and the truck died. I replaced the alternator and starter, it sits just below 13 at idle and 13.5 at speed. Now when I turn the AC on or literally any electrical using components it tanks it to about 10 volts. Is there anything else I should or can replace to fix the problem and get the battery light off?
 

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It should be around 14.5 under load. Check the voltage regulator. It might be the cause of your troubles
 
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It wouldn't be the first time that a rebuilt alternator failed as soon as you put it onto the vehicle.

I went through 3 alternators one time on a different vehicle before I got one that actually worked.
 

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It wouldn't be the first time that a rebuilt alternator failed as soon as you put it onto the vehicle.

I went through 3 alternators one time on a different vehicle before I got one that actually worked.
Yes, I had the same experience. Finally after I brought the third one back, the parts store gave me a new one for the same price, and that one worked.
 

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Replace alternator and regulator at the same time. I have seen where one burns up the other. I made that vicious circle three or 4 times once.
 

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I've noticed lately that more than a few alternators I have replaced are only coming to about 13.5-13.8. I'm not sure why but they seem to be able to keep the battery charged and handle the load put on them. My preference is to see the alternator around the 14.2-14.5 area. Verify that your grounds are in good shape - no corrosion build up where they attach to the frame or engine.
 
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