Question about 2005 Chevrolet Avalanche

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Charging system Question

When I first start the truck, it shows around 14.5 volt on the meter. After a few miles of driving, the meter drops to around 13 volts. It stays there even if I turn on the lights and air conditioner. The next time I start the engine, it again shows 14.5 volts for the first few miles of driving then the meter again drops to around 13 volts. Is this a normal condition or do I have a charging system problem to address?
2005 Avalanche with 5.3 litre engine
thanks for the help
D Osburn

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  • dbosburn Nov 22, 2008

    Why would the charging system always start at 14.5 volts then drop after a few miles? Could it be that heat is reducing the output or that the battey becomes recharged after the starting drain? It always starts at 14.5 for a few miles then drops to around 13. interesting!!


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This is within "normal ranges" however it is an indication of wear on your alternator. If you start seeing a slow but steady decrease in your voltage it is probably time to check out the charging status of the alternator on your vehicle.

Posted on Nov 22, 2008

  • Lance  McKinney
    Lance McKinney Nov 24, 2008

    It is very interesting I could only theorize as to why it starts normal and then decreases. Probably has to do with the dynamics of the alternator coils that have a flat spot that doesn't show up until the coils expand with heat. Good Luck


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