Time to replace battery? Upgrade to AGM?

SOC and temp is more of a function of the charging system and parasitic load and time since the vehicle was last running and for how long. Than a battery health indicator.
 
Yesterday I took a different battery to the FLN(NAPA)APS to have it tested and was told their battery tester was broken and the counter guy didn't offer when it would be fixed or replaced. And NAPA is the only place I feel like they kinda know some things.
Sorry to hear this. NAPA Legends have always been good for me that's why I recommend them.
 
On a regularly used battery, 12.54 is too low. I just recently been through the same thing on two of my vehicles both group 65 batteries. . I would bet if you had it tested, you will find the cranking capacity is far below the spec. for that battery. Both of my old batteries were atleast ten years old and rated at 850 CCA's. One tested 525 and the other 540 CCA's. Both new ones (850 CCA) tested above 960 CCA.

I would go the flooded battery route.
 
Dropping a Everstart Platinum AGM in our 2012 Chrysler van this weekend 👍 since the dealer wanted $430 for a “Mopar battery” 😂 they are bleeding us enough for a water pump, t-stat and heater hose replacement.
 
IMO, I would put back whatever came out, which in you're case was an FLA. My Honda came with an original FLA, then when that died, I put an AGM in it. The AGM didn't like it. My Honda has a charging system built for an FLA. The AGM was not being charged correctly, and had to go back with an FLA. Had an older car that consistently charged at 14.5 or so volts. Got lucky, and it fit in that car. So far, no problems with the AGM in the older car.
 
I just did a 200 mile highway trip yesterday in the 2021 GMC with the 6.6 gas engine (empty) and decided to check the resting voltage of the battery this morning and it's 12.54 volts. The truck is used to tow the travel trailer all over the country and I don't want to deal with a no-start - replace battery deal out in a remote campground somewhere. The battery is original and is a group 94, 720 CCA and GMC lists a 94 and a 48 as replacements. I have a decent Klein multimeter and tested directly from the terminals so that's a good number. Also would an AGM equivalent like an H6 be a good upgrade? My standard SOP with batteries has been replace it when the first slow crank is noticed but maybe not in this useage. I've been following the ongoing "no more AGM" thread and as usual varying thoughts about AGM vs flooded.

So, replace almost 5 YO battery now and go to AGM or replace with another flooded L/A?
I'd assume there is "smart" charging system on that, so it probably shuts the alternator off fairly often, and you might have just pulled in and stopped as it had been running off the battery for a while?
I was pretty shocked when I plugged in my scanguage and saw the smart charge system on the Impreza take the battery down to ~11.8V before it started the alternator again! I had an alarm programmed for 12.0V from when I had the scanguage in my Focus with a broken smart charge system, so I was very surprised to hear the alarm go off in the Impreza.
If you run the headlights then the smart charge system may keep the alternator going full time, like it does in the Impreza?
Anyways, my battery started the car in a couple -32C mornings, so I guess it was charging enough!
 
On the recommendation of @DCDG I ordered a battery tester and it came today and I got this so it looks like a new battery is going in before we go anywhere.

38451b3c-9c05-4e03-aef2-d4bc31477fca~1.webp


This is the OEM battery: Interesting the replacement is 765 CCA.
PXL_20260305_140135492.webp
 
On the recommendation of @DCDG I ordered a battery tester and it came today and I got this so it looks like a new battery is going in before we go anywhere.

View attachment 327201

This is the OEM battery: Interesting the replacement is 765 CCA.
View attachment 327202
I’m glad you’re enjoying your new tool! You’ll notice on a new replacement battery in good health the CCA will possibly read higher than manufacturer specifications. I purchased a 525CCA it read 538 after putting it on a charger it read 551CCA. If you have a charger and your new battery isn’t topped off I’d recommend topping it off.

Have you tried putting your current battery on a 8-10A charger? Might be surprised I heard stories from a co worker with a sierra how he doesn’t drive enough and the GM charging system float charges the battery and his battery never gets enough charge long story short he was going through batteries every 1.5-2 years now he periodically charges on a battery charger and get 3-5 years.
 
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On the recommendation of @DCDG I ordered a battery tester and it came today and I got this so it looks like a new battery is going in before we go anywhere.

View attachment 327201

This is the OEM battery: Interesting the replacement is 765 CCA.
View attachment 327202
Great tester. I got one a few months ago. It cost me money however. I ended up buying two batteries and a third one is in the near future....:ROFLMAO:
 
I just did a 200 mile highway trip yesterday in the 2021 GMC with the 6.6 gas engine (empty) and decided to check the resting voltage of the battery this morning and it's 12.54 volts. The truck is used to tow the travel trailer all over the country and I don't want to deal with a no-start - replace battery deal out in a remote campground somewhere. The battery is original and is a group 94, 720 CCA and GMC lists a 94 and a 48 as replacements. I have a decent Klein multimeter and tested directly from the terminals so that's a good number. Also would an AGM equivalent like an H6 be a good upgrade? My standard SOP with batteries has been replace it when the first slow crank is noticed but maybe not in this useage. I've been following the ongoing "no more AGM" thread and as usual varying thoughts about AGM vs flooded.

So, replace almost 5 YO battery now and go to AGM or replace with another flooded L/A?
Flooded
 
I charged it overnight at 10A with the smart charger and still got this.
View attachment 327232
I know you did all you can to revive the battery one last thing go out a 30 min drive and retest I am curious what it'll read. I charged my battery the charger said full when I checked it it did read 97% as well went for a drive come back retested and had 100% charge. health went back up again my battery was new and healthier to start off with. But if you got a half hour to spare plus a retest.
 
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