Group 31 battery replacement.

[rdracer66]

So it's sadly time I believe to replace my old diehard platinum AGM group 31 battery. I suppose it could be the alternator but I don't think so. I don't drive her as much as I use to since I mostly work from home these days. Last week it would not start after sitting for 3 weeks. I can't seem to get it fully charged using an external battery charger. I forget if it's considered a marine battery or not but I've tried charging it using the standard and also the marine setting on the external charger. I probably should have hooked up a trickle charger to it but hind sight is 20/20 right. I bought this battery probably 10 years ago so it's had a good life starting my rig and running my fridge which is the reason I got this battery in the 1st place. So time to get another battery but question is which one? I think another group 31 would be good as I would like to start doing some more car camping this coming summer. But I'm not opposed to going back to the stock size battery. Only issue is I'm not sure where the old battery tray went and I currently am using the CBI 3rd Gen Toyota 4Runner Battery Tray (Group 31). I also had to buy a kit to extend the battery cables in order to use this group 31 battery. So going back to the stock battery would probably give me very long cables now. So any suggestions on what you guys would do?

 

[Endlessblockades]

Sounds like you've carved out a niche for yourself with the Group 31 (which seems to have a fairly large footprint). Not that it helps at all, but I have been running a Group 48 (DH6) Optima for a year. It fits the stock cable lengths and factory plastic tray but is just a bit less tall (1/4") than the stock securing bracket works with. I just use a piece of wood to make it work. You could always compare dimensions at a site like this:

BCI Battery Group Size Chart

 

[rdracer66]

Thanks for the link. At this point I might just start looking for another group 31 battery question is which one. I'm leaning towards this one

Advance Auto Parts - Down for Maintenance

 

[Endlessblockades]

Thanks for the link. At this point I might just start looking for another group 31 battery question is which one. I'm leaning towards this one

Advance Auto Parts - Down for Maintenance

2 hour and 40 minute reserve is pretty darn good for that price! Nearly 14" is pretty big but if you've got that tray for it, why not.

 

[pluton]

$245 is a low price these days for a group 31 AGM. The "high end" brands like Odyssey Extreme are at over $550. I'd try it, but maybe rig a trickle charger or occasionally charge it with an AGM specific smart charger.

 

[alia176]

Here's another datapoint on the Die Hard Platinum AGM batts. I went through couple of them in my '96 80 series landcruiser and this was due to the ALT not outputting high enough voltage to satisfy this particular AGM. I've since switched to lead acid batts but though I'd pass this along. Make sure your ALT is outputting 14.4 - 14.8 vdc.

 

[brillo_76]

When Money is no object anymore...
Car Batteries Archives - Dakota Lithium Batteries

really been coming down in costs in the last few years.

 

[rdracer66]

Here's another datapoint on the Die Hard Platinum AGM batts. I went through couple of them in my '96 80 series landcruiser and this was due to the ALT not outputting high enough voltage to satisfy this particular AGM. I've since switched to lead acid batts but though I'd pass this along. Make sure your ALT is outputting 14.4 - 14.8 vdc.

I did actually see something about this when I was doing some research just recently. I know for a fact my alternator was not putting out enough but I guess I just got lucky as I've put this battery through the ringer in it's first 7 years of life using a fridge and what not. I think where I went wrong mostly is the past couple years when I've not been driving her that much I should have been using a trickle charger.

 

[pluton]

I had a group 34R Odyssey that I installed when I got my 4R in 2013. Replaced it with another Odyssey 34R in 2020. The old one still started the 4R, but it's capacity was about half of new because (presumably) of the low charging voltage from the stock alt. For those 7 years, I drove it regularly around town with the occasional longer trip. I'll know how much the voltage booster (acquired in 2022) helped when I pull this battery out ....in 2027!