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Group 31 or Dual Batteries?

RamRod

Well-Known Member
Messages
3,914
Location
AB, Canada
Hey guys I am hoping to get some input on which way to run when I go to switch up my electrical setup to accommodate the new fridge/freezer I just ordered (Engel mr40).

My other electrical needs are quite light as I have all LED offroad lights and will be converting as many of the remaining OEM lights over to LED where possible.

I can fit a group 31 with minor trimming and I am leaning towards this option since it's the easiest but I loose the benefit of having a separate starting battery.

I can go to a dual battery setup with a bit more work, but that also means that I need to get a dual battery tie down/cage and then all the electrics, switches and wires to get it all hooked up, which will end up costing a lot more in the end, but will have added security of a separate starting battery and slightly longer run time.

One more piece of the puzzle, I recently upgraded my alternator from a 140 amp unit to a 160 amp unit.

I am leaning to run a group 31 due to the easy conversion, then picking up one of those little lithium ion jumper packs to negate the disadvantage on not having the separations for starter and house batteries.

One last reason is am thinking of going the group 31 route is that in the future I can expand the system if I am finding that I don't have enough power by adding a second group 31 under the truck bed (AGM so it can be mounted on its side).

Thoughts?

Ps- next summer we are heading down to baja with the truck and that's why I am getting all of this setup now to have a trial period to get things sorted out
 

rascole

Well-Known Member
Messages
2,850
Location
Bellflower, CA
I run dual batteries with no switches, just a quick disconnect. When I overland, I disconnect the spare and my Dometic fridge can run for 3 days before the low voltage cut off. If a battery goes bad I have a spare.
 

CaseyS

Well-Known Member
Messages
755
Location
Louisiana
I put a group 31 in and it only stayed in for a day. Nothing wrong with it, just cosmetically didn't look right. It was tall and looked out of place without the factory battery cover.

I ended up going with a custom fabbed battery tray and dual group 34s. Looks much better IMO.
 
Last edited:

derian06

Red Rockett
Messages
1,866
Location
Madison, AL
I'm running the powerbastards 250amp alt with a Odysseus battery up front and a small extra battery in the back. It powers everything very well. 12k winch, light bars, 4200wrms sound system.
 

GreatDaneHummer

Well-Known Member
Messages
994
Location
Chicago
I have an Indel B 51L fridge and an ARB. This last trip to the Badlands I used the Indel B and had no issues after I ran a dedicated power line to the rear. I use dual battery optima's and with a 60 amp pull total they held up all night without running the motor/alternator so I would suggest using the dual batteries. I did the National Luna Dual Battery setup now from EquipT to be able to run the 1 battery fully dead and still have it auto switch over to start the H3 in the morning. This is a safer way if you get too plowed to remember to turn your stuff off.
 

GreatDaneHummer

Well-Known Member
Messages
994
Location
Chicago
Efan setup and dual battery.jpg They fit just fine but I later wrapped them in heat insulation due to they where melting the engine harness covering on a hot summer day.
 
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