I have replaced the alternator on my 2011 chevy traverse 2 times in the last 8 months. I have replaced the battery on it 4 times. When I am driving long distances my battery will start to lose power. I go to the auto parts store and they tell me that it is a bad battery. My mechanic is telling me that it isn't the battery that it's the alternator that stops working, but when the car is restarted the alternator acts normal. Why would the alternator just stop working while driving on long distances, and why would the auto parts store think it was the battery?

 

What size alternator do you have?

 

Check all your electrical connections. Sounds like you might have a loose or bad connection somewhere that intermittently breaks connection.

 

Or he's pullng 120 amps off an 80 amp alternator.

 

Do you know how to read/use a Voltmeter ?
Without some imperial evidence of your problem, you're not going to make much headway on this.


You need to know.....


1: What is the "resting" Voltage of the System ? (Like in the mornings, not started overnight)
2: What is the Operating Voltage when running (when the problem isn't happening)
3: What is the Voltage Reading while running, when the problem occurs ?
4: What equipment do you have on when the problem occurs (A/C, Radio, other)


Give us this, and we'll go from that point

 

And to add to this advice, checking the voltage with everything on, lights, a/c everything

 

An excellent point, thanks for the addendum