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Discussion Starter #1
Just bought and installed an Everstart Maxx H6 battery from Walmart, gave it a charge but this morning it's ready 12.16 volts. Shouldn't a new battery be up around 12.6 or so? I don't see anything that would be draining it. Should I return and replace?
 

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not running that is o.k,should jump up to 13.5 or so running
 

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Just bought and installed an Everstart Maxx H6 battery from Walmart, gave it a charge but this morning it's ready 12.16 volts. Shouldn't a new battery be up around 12.6 or so? I don't see anything that would be draining it. Should I return and replace?
Sounds a bit low to me, but open-circuit voltage (what you're measuring) doesn't tell you much about the battery's condition. The voltage needs to be tested under load, so at a minimum I'd have the store do a load test and see what happens from there.
 

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Just bought and installed an Everstart Maxx H6 battery from Walmart, gave it a charge but this morning it's ready 12.16 volts. Shouldn't a new battery be up around 12.6 or so? I don't see anything that would be draining it. Should I return and replace?
a new battery that has been charged to full capacity should read 12.6 or 12.66 volts depending on the accuracy of your meter. This does not mean your batteries are bad, just that they are not charged off the shelf which is not abnormal. I would take the truck for a 45 minute drive on the highway, park it for an hour or two, then hop in, dont start it, turn the high beams on, and the blower on high for 30 seconds then check the voltage, if your still not around the 12.4-12.6 range then i would start to worry about the batteries. Note that with the battery isntalled in the truck, you may never see a perfect 12.6. anything over 12.3 - 12.4 is good in my book.


Edit:

To answer the question that is likely to come, the reason you turn the blower and the high beams on for 30 seconds with the truck off is to bleed off any surface charge on the batteries. Its not uncommon after a battery comes off a charge, especially when that charge is from a 200+ amp alternator, for there to be some extra charge in the battery that would read over 13V on a meter, but the battery cant sustain that voltage for more than a few seconds since the chemistry prohibits it, turning the lights and blower on bleed off that extra charge and give you a better reading of what the battery voltage actually looks like. Were you to skip this step after a fresh charge, even a bad battery could read over 13 volts and you may incorrectly assume it is healthy. This step is not required if you are using a true load tester as it will bleed off the extra charge, but if your just using a high resistance meter to test for voltage it does not have sufficient load (almost none in fact) to bleed off the surface charge.
 

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Discussion Starter #6
a new battery that has been charged to full capacity should read 12.6 or 12.66 volts depending on the accuracy of your meter. This does not mean your batteries are bad, just that they are not charged off the shelf which is not abnormal. I would take the truck for a 45 minute drive on the highway, park it for an hour or two, then hop in, dont start it, turn the high beams on, and the blower on high for 30 seconds then check the voltage, if your still not around the 12.4-12.6 range then i would start to worry about the batteries. Note that with the battery isntalled in the truck, you may never see a perfect 12.6. anything over 12.3 - 12.4 is good in my book.


Edit:

To answer the question that is likely to come, the reason you turn the blower and the high beams on for 30 seconds with the truck off is to bleed off any surface charge on the batteries. Its not uncommon after a battery comes off a charge, especially when that charge is from a 200+ amp alternator, for there to be some extra charge in the battery that would read over 13V on a meter, but the battery cant sustain that voltage for more than a few seconds since the chemistry prohibits it, turning the lights and blower on bleed off that extra charge and give you a better reading of what the battery voltage actually looks like. Were you to skip this step after a fresh charge, even a bad battery could read over 13 volts and you may incorrectly assume it is healthy. This step is not required if you are using a true load tester as it will bleed off the extra charge, but if your just using a high resistance meter to test for voltage it does not have sufficient load (almost none in fact) to bleed off the surface charge.
Great tips, will give that a shot. Headed to Walmart tomorrow so will have them do a load test too, sure want to make sure my brand new battery mfgd in July is a good one!
 

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Great tips, will give that a shot. Headed to Walmart tomorrow so will have them do a load test too, sure want to make sure my brand new battery mfgd in July is a good one!

Im quite sure the battery is fine, its very rare to get a bad battery off the shelf these days. However its still a good idea to make sure its good before your outside the return period so do the tests and see how it goes. I would bet though that the batteries are totally fine unless there is some other issue with the truck that is so far undocumented.
 

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Discussion Starter #10
I only have 1 battery. It was totally dead today, tried charging it all day but could only get up to 11 volts. Had to jump the truck with my wife's car, headed to Walmart tomorrow. I don't know of anything that could have drained the battery overnight, no lights or radio left on, what else could drain it?
 

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I only have 1 battery. It was totally dead today, tried charging it all day but could only get up to 11 volts. Had to jump the truck with my wife's car, headed to Walmart tomorrow. I don't know of anything that could have drained the battery overnight, no lights or radio left on, what else could drain it?
wait, you only have 1 battery total on the truck? what happened to the other battery?

if you mean that you only replaced 1 of the 2, then you need to replace both together or the old will kill the new.

it doesent actually take that much to kill a single battery over night, especially considering the demand our trucks put on the battery to turn the starter. It would take a little as a glove box lamp or something getting stuck on (super common on the old chevy trucks) to kill the battery over night to the point where the truck just clicks at you. If you only have 1 battery, you should probably return that one and pick up 2 and put both batteries back in. every duramax ever built left the factory with 2 batteries installed.
 

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I only have 1 battery. It was totally dead today, tried charging it all day but could only get up to 11 volts. Had to jump the truck with my wife's car, headed to Walmart tomorrow. I don't know of anything that could have drained the battery overnight, no lights or radio left on, what else could drain it?
Any aftermarket accessories? You really need to load test the battery and see if it is good. I'm not sure if you did that already. You could have a bad cell in the battery.
 

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Discussion Starter #13
Any aftermarket accessories? You really need to load test the battery and see if it is good. I'm not sure if you did that already. You could have a bad cell in the battery.
I don't have a way to load test, that's why I'm headed to Wally World tomorrow.
 

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I don't have a way to load test, that's why I'm headed to Wally World tomorrow.


you can perform a load test with just a multi meter by using the trucks electronics as a load, turn the blower motor on, all the head lights, fog lights, rear window heater, should get you at least a 50-60 amp draw and should give you at least some idea of the health of the battery, the voltage should stay in the 12's through this process. If you have power seats you can move them to add load too, same with seat heaters. Its not as reliable as a real load test, but its good enough for a ball park idea of the battery health. If it fails this test it will surely fail a real load test, if it passes this it could still fail a load test since they can apply larger loads, but its likely to be good enough to start the truck still.
 

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Discussion Starter #16
Well, I left a maintainer on my battery all night and this morning battery was reading 9.74 volts! Why would a battery drain like that? Anyhow, got my wife to jump start my truck and headed to Walmart. Counter lady took out her battery analyzer (battery still hooked up in truck) and it read correct volts and amps but said 'need charge'. What? So I asked for a service guy, he comes out, starts it up (I had driven it for about an hour), runs a test to check alternator (13.5 volts) but gets the same message. So he takes it into a bay to hook up the charger and re-run the test. So I go shopping, come back and counter gal says 'battery is good'! I said no way in hell (not quite my exact words) that this battery is good. Let me talk to a manager! So she goes behind the door and says manager will be right out. 10 min. later, no manager and she says that they are removing battery from truck and will re-charge and re-test, will take another hour. Great. So I go buy some crap I don't need to kill the time then head back to the service desk. She now says the test machine says to replace the battery. FINALLY! I briefly talked to the service guy and he says something like 'I think our charger is a piece of crap' and kinda insinuated that he didn't think the battery was bad even though that's what the tester is now saying. Anyhow, I now have a different battery so 'hopefully' this one will be OK. I'm usually a pretty calm person but I was fixin' to raise hell if they didn't give me a new battery, and they would have lost a lot of my future business over a $120 battery.
 

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Discussion Starter #17
UH OH, there's a problem somewhere. I just checked my battery, only been on the truck 6 hrs. and voltage is down to 11.6 and truck won't start. What could be causing the drain? Lights are off, radio's off, A/C is off. What else could be causing this?
 

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Discussion Starter #18
Well, do I ever feel like an idiot. After researching some more I pulled the radio and amp fuse (even though I don't have an amp) hoping this was the fix. Was able to get the truck started and went for a drive. Came home, opened the hood and something hit me about everyone saying there should be a 2nd battery on the passenger side. And YEP, there it was! Don't know if it's bad or not but gonna go buy a 2nd new one tomorrow. Thoughts that it might have been the cause of draining my new one even if the old one is 'good'?
 

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Missing obvious things gets A LOT worse as you get older. You've got much more of this to look forward to.

Denial and deception are the best coping resources.
 
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