when to replace a battery

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The battery in the pt cruiser is about 5yrs old it's a Napa legend battery. When cranking the volts go down to about 9.5v. Under my carbon pile load tester it goes down to about 10v when doing the loas test. Would you leave it be or get a new one ?
 

JHZR2

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Well if you know your starter current draw, you could calculate impedance and know exactly. Put a dc current clamp on the starter line, report back current with that voltage drop, and the original battery spec, and we will know. Data is power.
 

gathermewool

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It all depends on your threshold for pain. Worst case, I'd have to leave work and get her a new battery if it died at work or home for her car, and I'd have to wait for her to get off work or get a ride from a buddy to get a new battery if mine died (assuming it needed it and a jump didn't make sense.) So, for me it makes more sense to just wait for it to die or get to the point where it shows signs that cause me concern for our safety or the integrity of the charging system. Otherwise, I plan to go until it dies.
 
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I can tel you on my 2012 Nissan Rogue the factory battery died exactly 2 years oh me owning it. It gave me zero warning. Started fine like always after a bike ride 90 miles from home. Stopped off at grocery store on way home and it would not start. I could not believe it was the battery. Got a Deka and the dealer says plan to replace in modern cars and especially in Floridas heat every 2 years.
 
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It is time for a new one Ram Man. But I agree, after the 4 year mark is borrowed time. You can milk them in the 5th winter if you use a 0W synthetic to lower the cranking amps drawn on a cold day and if you can walk to Walmart to get a new JC battery and drop it in. If it means just being 45mins late one Winter day, milk it. At 5 years I'll change mine, then get a new Dekka and trickle charge it for a day then put it in the car. That way, 2 batteries and the car is 10 years old. I don't like scrapping a car with a brand new battery in it, which happens to people a lot.
 
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9.5 volts and neither one of m,y car would start due to the relays dropping out. Anything under 11v when cranking would be suspect to me.
 
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This might help ..it was posted a little earlier http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3489287/AAP_$50_off_$100+_first_2000_c
 
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Originally Posted By: ram_man
The battery in the pt cruiser is about 5yrs old it's a Napa legend battery. When cranking the volts go down to about 9.5v. Under my carbon pile load tester it goes down to about 10v when doing the loas test. Would you leave it be or get a new one ?
I assume you did 1/2 the CCA for 15 seconds (until it beeps). What did the temp compensated scale on the tester say? If its on the border between good and replace then replace. For most people a car battery costs about $20/year. ($100 for 5 years). So if you squeeze an extra year you did not save $100 (total cost) but only $20. It will of course fail when its dark, snow is falling and its so cold the wrenches stick to your bare skin. And you wife will say she told you in Sept to get a new battery.
 
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I'm running a 7 year old battery... fires right up, never had an issue. If you take good care of a battery and don't leave a light on and drain it down all the way they seem to last longer.
 
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I've had them go bad in as little as 3 years, and have had several Motorcraft batteries go 8 years or better. If they appear to sound weak when cranking, I'll get them tested. If they are even borderline, I replace. I would rather deal with a bad battery at my leisure, then have to buy the first thing available in an inopportune situation. Usually find the best discount code, and buy from AAP on line.
 

gathermewool

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For those who have issues with batteries lasting more than 3-4 years, I've got a couple of questions: 1. Is this consistent, meaning battery after battery fails within this time frame? 2. Which battery? Do you always buy the cheapest, middle of the road, or the most expensive AGM battery you can find? 3. What's your typical engine-off behavior? Do you or your S.O. listen to the radio after you get to your destination and turn the engine off, leave the lights on while you read for a bit, or have any other frequent occasions where you're eating into your battery's reserve capacity? 4. Do you drive short-trips often, or have a lot of start-stop cycles with minimal highway driving? These questions are for the OP, as well as any one else who wants to contribute.
 

JHZR2

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Batteries will not last because of a few things: 1) heat, both ambient time averaged (eg Arizona vs Idaho) and underhood. 2) number of cycles, both deep to depletion, and shallow. 3) use of electronics such as dome lights, courtesy lights, etc when the engine is not operating.
 
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I'd rather replace. For every old battery we try to milk another week/month/year out of there's an alternator and voltage regulator struggling to keep up and all your other systems not receiving full draw. For a hundred bucks every three years to have a fresh battery in the car, I don't see how it's even a consideration. But then, I'm the guy cutting the tray of my Hyundai to make room for a battery fit for a Lincoln. Once that puppy is charged up, nothing in the Hyundai is going to ever have that battery breathing hard. When it comes to batteries, I'm all in for overkill. There is no substitute for CCA.
 
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THey were saying on the news this summer has set some records with the persistent heat, etc. Heat will kill the battery, it will just completely die as soon as it is most inconvenient. Change it while it is warm and sunny or you'll end up wet and cold.
 
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