sible Battery Issues..

WVI · Sep 25, 2026

We've traveled from S.Illinois, to Spokane, WA towing r 37ft travel trailer.
Lately, there was a couple times my mind said, "sounds like its turning over a bit slow..I wonder if there's a battery problem?"
We've been here a few days now.
I have done some short around town trips, via hiway and surface streets.
This AM, when I started it here in the rv park, just to run a bunch of stuff up to some rental cabins in the park, there was a message on the DIC about "service system, low battery" It happened twice, but after the third run, maybe a total time running of 15 minutes, I dont get the message.

The iDash shws the batts at 12.8 volts resting and just over 14 volts running.

I have a service appointment at a local dealership Monday AM, but I'm looking for opinions/thoughts as to if it may be just batteries...there's so much electrical on this thing, I'm a bit leary of the dealer route, but dont want to just throw new batts in unnecessarily.

about 41000 miles on the trk, and the batts look to be the OEM GM.
Thoughs appreciated.
TIA

owns 2023 GMC 2500

gemarsh · Sep 25, 2026

You would not be the first on here to have batteries go bad. Even newer than a '23.

12.8 is good, but need to know what it reads when cranking or a load test done.

It's not my dime, but replace both, if one tests bad. You'll thank me in 6 months.

john151ama · Sep 25, 2026

I have a 2024 and had similar issue a couple times. I replaced mine earlier this year and no problems since. I think my OEM battery was no good. Replaced with this one in February and it’s solid. (I have the 6.6 gas / 1 battery)

R467X · Sep 25, 2026

Unlikely that GM will replace your batteries for free. Go to autozone and have them test your batteries. If they're bad - replace..

WVI · Sep 26, 2026

Thanks for the replies.
When look at the connectors under the baterry cover, it makes me wonder if its safe to let Autozone or anybody test them in the truck.

gemarsh · Sep 26, 2026

WVI said:
Thanks for the replies.
When look at the connectors under the baterry cover, it makes me wonder if its safe to let Autozone or anybody test them in the truck.

Yeah that battery distribution fuse block looks scary, but it's actually less than 100 bucks.

I understand where your concerns would be, letting Joe shmoe test your batteries, but even a auto zone groupy would have a hard time causing an issue.

R467X · Sep 26, 2026

WVI said:
Thanks for the replies.
When look at the connectors under the baterry cover, it makes me wonder if its safe to let Autozone or anybody test them in the truck.

You can always find a speciality battery shop too, maybe Costco since they sell batteries and have them do it. Or buy a tester off Amazon with one day shipping and do it solo

WVI · Sep 26, 2026

Thanks for the replies.
I had considered geting a tester at one time. I can see where it would be handy.

WVI · Sep 29, 2026

UPDATE
I had the batteries tested this AM.
Drivers side was bad, so I had them stop there and bought two new ones, which I intend to install tomorrow am.

Thanks again for the assis4folks!
Be safe out there.

skw774 · Sep 30, 2026

2024 bought in december 2023. new batteries a month ago. i also noticed slow start sound after sitting for 2 or 3 days

pinebaron · Oct 1, 2026

Although GM replaced both batteries under warranty (caused by a failed GMC software update) ,now more than a year ago, I keep them charged using a large floor charger since I don't drive the truck a lot. In addition, I used the battery recondition option last week, using a different charger. As we head into winter here in WA and we frequently travel to Whistler BC (too much snow and adverse conditions can occur ), I can't afford to have any battery issues.

WVI · Oct 1, 2026

I got both batteries in this AM and cleared a bunch of codes that co e along with that and she starts quick now!!

WHAT4-74 · Oct 5, 2026

WVI said:
We've traveled from S.Illinois, to Spokane, WA towing r 37ft travel trailer.
Lately, there was a couple times my mind said, "sounds like its turning over a bit slow..I wonder if there's a battery problem?"
We've been here a few days now.
I have done some short around town trips, via hiway and surface streets.
This AM, when I started it here in the rv park, just to run a bunch of stuff up to some rental cabins in the park, there was a message on the DIC about "service system, low battery" It happened twice, but after the third run, maybe a total time running of 15 minutes, I dont get the message.

The iDash shws the batts at 12.8 volts resting and just over 14 volts running.

I have a service appointment at a local dealership Monday AM, but I'm looking for opinions/thoughts as to if it may be just batteries...there's so much electrical on this thing, I'm a bit leary of the dealer route, but dont want to just throw new batts in unnecessarily.

about 41000 miles on the trk, and the batts look to be the OEM GM.
Thoughs appreciated.
TIA

owns 2023 GMC 2500

just replaced mine on a 22 3500 HD AT4 after similar issues. Batteries are not what they used to be, 5 years is life expectancy usually and that equates to about 40-50k miles too. theyre awkward to do as well and a second set of hands makes it easier.

gemarsh · Oct 5, 2026

WHAT4-74 said:
just replaced mine on a 22 3500 HD AT4 after similar issues. Batteries are not what they used to be, 5 years is life expectancy usually and that equates to about 40-50k miles too. theyre awkward to do as well and a second set of hands makes it easier.

Just replaced 3, stud top interstate batteries out of one of the semis. Dated 4/2016, will never probably see that again!

I use CAT branded batteries from my local dealer on whatever I can get them to fit in. No idea who makes them for CAT, but a group 32 is heavy as hell.