2009 V10 Dual Factory Battery - Adding House Battery ??

[Cummins_expo]

After many hours of reading and researching, I have finally decided to post my question.

2009 v10 Cutaway Chassis
Supreme Box
Factory added 2nd frame rail battery

It appears I have the equipped 2nd battery isolator in the engine bay- 2nd Battery in box under passenger side of frame rail

I am wanting to add a bank of batteries ( house batteries ) AGM. Can I tie into the underframe rail 2nd battery directly? Would I need to add a second ACR or some kind of additional switch/relay for the house batteries to charge and disconnect when the vehicle is off?

Do I need to run an ACR standalone of the factory ACR? It would be nice to not have to make a run all the way into the engine bay. Equally if I tie directly into the frame battery will it matter if I am running AGM vs the I assume lead factory batteries

 

[Bikersmurf]

What purpose does the 2nd battery currently serve?

Is the factory isolator a diode type or an ACR?

I'd not mix AGM & lead acid in one bank. They have different charging needs.

I'd be leaning towards eliminating the factory 2nd battery and replacing it with your AGM bank. Or if it's needed for starting, create a whole new bank for house batteries, and isolating it with a Blue Sea ACR.

 

[Cummins_expo]

What purpose does the 2nd battery currently serve?

Is the factory isolator a diode type or an ACR?

I'd not mix AGM & lead acid in one bank. They have different charging needs.

I'd be leaning towards eliminating the factory 2nd battery and replacing it with your AGM bank. Or if it's needed for starting, create a whole new bank for house batteries, and isolating it with a Blue Sea ACR.

My buddy suggested the same thing- eliminate the 2nd battery an put in the house bank in its place.

Is the factory isolator a diode type or an ACR?
- Not 100% sure as the switch is burried in the engine bay- But based on this info somebody posted I am guessing an Diode- Can you explain the difference ?
"
The option Code is 634 $145 in 2008 you got ONE 78 AMP battery (main) and ONE 75 AMP battery.
The battery IS isolated from the main battery when the key is off.
The battery size is group 65 for BOTH of my Batteries.
The biggest problem of the batteries are how tall they can be and still fit in the box. 6 1/2 inches tall is it, unless you modify the box.
Aux batteries are available WITH and WITH OUT a trailer package.
Aux battery powers the trailer battery relay (if it has the FACTORY hitch wiring installed) when the key is on or off just like it does if you don't have an AUX battery but if the trailer drains the battery with the AUX battery the van will still start.
The relay for the Aux battery is mounted under the main battery.
The part number is F8UB-14088-AA
There is a diode in the hot in run circuit, it is mounted in the (as Ford calls it) BJB or battery junction box next to Fuse F5.
This wire on my van is White and Black 14 or 16 gauge and hooks to the small/energizer terminal of the relay.
One of the large terminals on the relay is another Black and White wire. This one is 8 or 10 gauge and hooks to a 60 AMP Fuse F20 in the BJB. This wire is Hot all the time.
The other large terminal has the feed wire to the Aux battery and a Red/Yellow wire that
feeds the trailer relays via BJB Fuse F24 20 AMPS and Fuse F8 40 AMPS.
(note without an Aux battery these two large wires have a jumper in them in at connector C145)

 

[Bikersmurf]

Diode isolation slows charging and reduces efficiency.

 

[dar395]

Or you could be on the cheap and use a simple Continuous Service Soleniod controlled by the key, there is room on the frame to add another factory box. I thing bikersmurf is correct don't mix but sometimes simple is also correct I have this simple system on the thread and it works great.

 

[Corneilius]

Or you could be on the cheap and use a simple Continuous Service Soleniod controlled by the key, there is room on the frame to add another factory box. I thing bikersmurf is correct don't mix but sometimes simple is also correct I have this simple system on the thread and it works great.

I love my continuous duty solenoid. Cheap and easy to install, and I hear it click when I turn the key so I KNOW its charging. Its also easy to jumper past if I need to jump start from house battery.

 

[rex_1_mn]

What are you running with your aux batteries? It would be awesome to be able to patch together a system with mostly factory components and wiring that powered the interior lights and power outlets off a second battery.

Why do they want to keep power to the Trailer wiring with the vehicle off?

 

[Cummins_expo]

House batteries will control -

Fridge
led lights
Couple of 12v power ports


From what I am gathering the largest battery that fits in a factory box is a group 65 - in theory, a group 27 is the equivalent but its taller

 

[dar395]

We sold our GMC to some friends and after they purchased it they upgraded to Golf Cart 6v batteries, this past summer traveling along side of them they ended up having a useful battery charge of about 35% greater than our 12v system. We are in the process of upgrading ours to 6v golf cart batteries along with 2-100w solar panels but even if I wasn't adding solar I would have still changed out the batteries. I ended up going with a set of "Deka" batteries from Lowe's as they not only offered them at a lower price but shipped them free and also gave a 10% for military service discount.

I think maybe you might want to look at the 6v options for greater power management while your in the planning stage for the system.