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AGM batteries and charging volts

cocodataco

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Hey guys wanted to see what everyone was doing to get the max volts to charge their AGM batteries.

I have done some searching on TW/google and it sounds like us guys with the 3rd gens don't have a way to boost our alternator voltage to charge AGMs. I will be putting a group 31 in my rig over the next few weeks and already own a battery charger that supports AGMs. But I would like to do something more than just hooking it up to the charger every month or so..

For reference the Odyssey AGM batteries needs anywhere from 14.1-14.7 volts, while our rigs output range maxes at 13.8v. Unlike the 2nd gen rigs that have an ALT-S fuse which you can place a diode to boost the volts our 3rd gens are ECU controlled.
 

XxMagpulxX

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So it goes in-between your alternator and spare battery. It will charge your spare battery at 14.4v. I have a dual battery voltage meter on both of my batteries and have had no problems with the alternator sufficiently charging the starter battery. Its been in my truck for over 2 years and the starter battery voltage is still holding 14v.
 
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MGM Aquaponic Tank

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Odyssey extreme
C28753FE-19A9-47F5-A947-168335827894.jpeg
 
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XxMagpulxX

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those are the ones I have in my truck
 
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cocodataco

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I'll be running a single group 31 in my truck so I don't believe the DC to DC charger would work for me. Thanks tho looks very interesting
 
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ForTheWin

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I'll be running a single group 31 in my truck so I don't believe the DC to DC charger would work for me. Thanks tho looks very interesting
Yeah, that DC to DC charger solution definitely answers a question you did not ask. KD Max can make a tune for you that basically amounts to an "AGM charging update." I cringe at the thought of paying hundreds of dollars for .5 voltage increase though. I have a nice agm battery.
 
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Sunsetsearider

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You or a tuner you use can bump the charging voltage up with VF tune. A nice bonus if you are tuning your truck. It's easy, I have done it myself.
 
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XxMagpulxX

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Yeah, that DC to DC charger solution definitely answers a question you did not ask. KD Max can make a tune for you that basically amounts to an "AGM charging update." I cringe at the thought of paying hundreds of dollars for .5 voltage increase though. I have a nice agm battery.

I agree with you about the thought of spending hundreds of dollars for that however, sometimes if you wanna do things the right way instead of half assed, it will cost money.
 
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Sunsetsearider

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I agree with you about the thought of spending hundreds of dollars for that however, sometimes if you wanna do things the right way instead of half assed, it will cost money.
When you get a tune it's for a lot more than increasing the alternator output. It was literally an afterthought when they discovered the settings for it. It is very handy though.
 
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