Battery Question

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Feb 27, 2017 | 12:30 AM

TacoSplitter

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Battery Question

Last month I did some work to my 06 6.0. To get it started and I went and bought a new battery and installed it on the passenger side. I know you are suppose to replace both batteries together but I'm just curious that since it has only been about a month do I need to replace the battery on the passenger side again along with the driver side or can I just replace the driver side battery and not have to worry about any issue later on. The truck cranks and runs fine now I am just wanting to replace the batteries/battery so that I don't have any problems in the future

Last edited by TacoSplitter; Feb 27, 2017 at 01:18 AM. Reason: More info

Feb 27, 2017 | 12:53 AM

Tedster9

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From: Waterloo, Iowa

It's important to replace both, connected together they make up a single battery, in electrical terms. If they are mismatched in terms of voltage or internal resistance the weaker battery will drag down the stronger one, excessive outgassing, etc.

Feb 27, 2017 | 04:01 AM

Bumblebee04

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Joined: Jan 2017

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From: Central Illinois

I understand most say to replace both at the same time but from a financial point of view i don't see the need if you check your batteries often which most do anyways. In my big rig theres x4 950 cca batteries. If I had replaced all 4 batteries over the past 1m miles I've thown on it every time one went bad I'd go broke. I've only had one alternator fail on it in that time. IMO as long as you're activity running routine preventitive maintenance checks you're good. Also I would recommend sticking with the same brand name batteries and cca. Just my $0.02.

Feb 28, 2017 | 06:15 PM

OneCylinder

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Joined: Sep 2014

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From: Jasper, Texas

No, this would only be a problem if one of the bateries was unable to hold a charge. Sears warrantyed one of my DieHards years ago. They didn't volenteer to give me two bateries when only one was bad and I wasn't going to toss out a perfectly good battery. Both those batties still hold a full charge. If you are concerned it has been sugested that the batteries be swapt from side to side once in a while since the heaviest draw is on the battery closet to the starter.

Feb 28, 2017 | 07:49 PM

FordBlueHeart

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Joined: Jan 2010

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From: Mesick

Have the one you currently have load tested. If you see a significant difference between the new one and this one, replace it as suggested.

Feb 28, 2017 | 07:50 PM

TooManyToys.

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Joined: Dec 2014

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From: Jersey Shore

The problem is with the depth of discharge of a battery because the reserve of the other battery is deficient.

It's more of an issue with 2 batteries then the load spread over 3 or 4. After a certain period of discharges a battery will start to lose capacity. It never again reaches "full capacity", but as long as it's capacity is not too far down, it can be paired with others. But as Tedster9 stated, the battery with the better voltage/capacity/resistance is stressed more. But at some time the stronger will balance down to the others with a shorter life then it would have with an equal partner(s). You can't get away from the chemistry of lead oxidation.