Community Forums

SuperDad · 03-04-2021, 03:03 PM

Can I replace my (2) group 27 house batteries with group 31 batteries? I have room for bigger ones.

twinboat · 03-04-2021, 04:51 PM

Yes.

2cyber71 · 03-04-2021, 04:53 PM

Yepper,
I like Interstate

Winemaker2 · 03-04-2021, 05:28 PM

If house battys and staying w FLA a pair of 6V GCs might be a better choice.
If AGM GP31s and GCs are very close in AH and deep cycle performance

SuperDad · 03-05-2021, 05:38 AM

I want AGM batteries.

Mark_K5LXP · 03-05-2021, 06:33 AM

If "bigger ones" includes additional headspace, you could go with taller batteries as well, giving you even greater capacity.

Mark B.
Albuquerque, NM

Gary RVRoamer · 03-05-2021, 11:56 AM

The "group" size just means different battery case dimensions - 12v is still 12v. Bigger cases have more lead plates inside, so can store more amp-hours. If you want AGM instead of flooded, by all means do so. You can get an AGM-type lead acid in most any case size. And in 6v golf car batteries as well.

Alpine36 · 03-05-2021, 02:21 PM

I switched from a pair of grp27 FLAs to grp31 Odyssey AGMs in our old Winnie. Very limited height clearance for CG2s, or I would have gone that route. The two Odyssey GRP31s gave excellent performance and are still going strong according to the new owner. They ran the furnace, 300w inverter for cpap and tv, and LED house lights for a weekend boondocking no problem.

birdsNboards · 03-05-2021, 04:50 PM

Sounds like a good idea to me. You'll want to check to make sure your onboard charger is compatible with AGM batteries. I believe they have some specific charging requirements. Sorry I don't remember the details. I climbed out of that rabbit hole once I decided to stick with FLA batteries. Once my TT comes out of storage I'll be upgrading from a couple of group 24' to group 31's. After scouring the net, the best deal I found was for some Duracell at Batteries Plus. https://www.batteriesplus.com/produc...ultra/sli31mdc

They've got the highest amp hour rating I could find in the size. With a sale and an extra 10% off for curbside, they should come in around $100 each. That is assuming you exchange your old ones. I found a battery with the exact same specs at NAPA auto but it's $30+ than the Duracell. The fact is that they are probably the same exact battery with different stickers. There are only a handful of battery factories in the US that make all the different brands.

rbTN · 03-05-2021, 05:14 PM

if you have the room, why not go with 2 12v golf cart batteries. True deep cycle and still 12v so get lots of amp hrs

you can get fla or agm from Trojan

Ohiomike · 03-05-2021, 05:46 PM

I would get 2 of the Duracell group 31 from Sam’s. They offer flooded and agm. I spoke to East Penn who manufactures majority of the flooded and agm batteries on market and they told me the 12 volt deep cycle are rated for same depth of discharge as he golf carts. I have 3 flooded and have been very happy. The agm version is $180 per battery. Cheapest you will find on market.

For the cost of agm from Trojan and some others I’d go lithium. The sams club batteries are priced right IMO.