Dual battery question

IconicTremor6.7

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Curious where you read that the 397 amp option for 7.3 says 2 alternators? The way I read the description for that package, it says “A 397 amp alternator...” which requires dual batteries. I read that as 1 alternator and 2 batteries
It’s 240 amp and a 157 amp alt making the 397 amp. It’s 2
 

CityHunter

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Pretty neat option. I didn’t get this on my lot-purchased truck, and don’t have any need for it, but I sure wouldn’t have minded the redundancy. If it’s possible to be notified when one battery drops below a specified charge threshold, that would be great. Hope the system is working out well for all of you with it.
 

Raspy

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If you get one battery, you get the passenger side battery. The driver side battery seems to be a support battery for the passenger side. The factory winch connects to the passenger battery. And the passenger battery has posts that allow you to hook up other loads. I installed an Anderson plug on the rear bumper to charge my trailer batteries. It is tied to the passenger battery with an 80 amp fuse and #4 marine wire. If you want to run wires to the back of the truck, it is easier to run them on the driver side because there is already a wire bundle running along that side and because the exhaust is on the passenger side.
 

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Undert0e

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Has anyone installed an isolator between the two batteries? I wonder how easy it would be to utilize the driver’s side battery as a house battery for my fridge, fan and camp lights.
 

ccw

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Has anyone installed an isolator between the two batteries? I wonder how easy it would be to utilize the driver’s side battery as a house battery for my fridge, fan and camp lights.
I haven't thought through the full complexities of adding an isolator to the factory batteries, but I can give you context of how they're wired.

The batteries are wired in parallel from the factory to provide additional amps for starting and high draw accessories (e.g. winch). They are grounded to various points on the chassis. There isn't a single positive cable connecting both of them. Instead they both have a positive wire running to the starter. That common point on the starter connects their positives together.

Of course since they're run in parallel they are matching starter batteries, not intended for deep cycle operation.
 

Avslash

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There is a company called Traxide out of Australia that makes a variety of isolator kits that could be fairly easily adapted to the Tremor.

Something like an Optoma yellowtop (combination of starting/deep cycle) would probably be best bet if going to an isolator, although there are much better battery brands out there IMO.
 

2020Tremor

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If you get one battery, you get the passenger side battery. The driver side battery seems to be a support battery for the passenger side. The factory winch connects to the passenger battery. And the passenger battery has posts that allow you to hook up other loads. I installed an Anderson plug on the rear bumper to charge my trailer batteries. It is tied to the passenger battery with an 80 amp fuse and #4 marine wire. If you want to run wires to the back of the truck, it is easier to run them on the driver side because there is already a wire bundle running along that side and because the exhaust is on the passenger side.
It is not too bad running in the passenger frame rail if you have fish tape. I also ran 2AWG wire and a Anderson plug for running my dump trailer as well as the BD backup light kit.

As for the factory dual batteries as others have stated there is no isolation so from a overly simplified standpoint it doesn’t matter much which one you connect to for small loads. That is unless you modified the system and add a isolator or ACR (automatic charge relay) to one of the batteries. For high current draw applications like a winch it’s best to connect positive to one battery and negative to the other to maximize capacity from both batteries.
 

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