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Time for a new battery?

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My 4S wouldn't start the other day. Put it on a trickle charge. It now reads 12.3v at the terminals. I thought I read somewhere it should be 12.6v for a fully charged battery.

I know there is a ton of threads on the subject. Price is not my concern. I'm thinking of just buying a new battery. Should I get a 48 or 49? Pepboys has a Bosch platinum 49 850cca. It's huge and 52lbs. Or Bosch premium 48 650cca and 36lbs.

BTW - This is not my DD.

Edited by Dario Campolattaro
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Hi Dario,

Been there done that. Not sure how much you're paying for the name "Bosch" but believe it or not, Wal-mart batteries, and Auto zone ones are rated very good according to consumers, and considerably cheaper.


I have a similar problem, but I "think" ? it's the alternator ? It's been plaguing me for years. Everything is fine on voltage readings for the first 3 or 4 miles (or about 7 or 8 minutes) 13.5 0r 13.6 , on the cigarette lighter gauge I   plug in, which is where it should be, then after the motor etc warms up, (and hence the alternator which gets hot also) it goes into the negative RED zone, putting out about 12.5- 12.8 volts, and not re- charging.


As you said , a LOT has been written about this dilemma, and frankly I'm just going to buy a new alternator and be done with it. Yes , it could be that infamous starter cable, and corrosion, and several other things, I'm aware of that, but I'm tired of this problem and I'm now 90% sure it could be the alternator. As far as the battery, try the ones above, and they ARE guaranteed just in case,  good luck ! Dave.

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  • Admin

If your battery is 4 years old or older... you need a new battery.

If your no-load battery voltage is under 12.5 volts... you need a new battery.

If a specific gravity test shows any cell lower than 1.210... you need a new battery.

If a specific gravity test reading vary more than .05 differences between cells... you need a new battery.

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A number of years ago a fellow forum member suggested Walmart batteries (cheap and 3 year no haste warranty). Bought one (OEM size) and about a year later I was having some trouble starting. So I rolled into Walmat, pulled out the battery, took it in, they gave me a new one on the spot no questions asked and no testing done, installed it in the parking lot and drove off. I later discovered that my electrical issue was a silly cheap USB charger and not the battery. There is always a Walmart nearby wherever we travel in Canada and the USA- best insurance IMO.


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