Dual Battery setup suggestions?

Hello,

Im new here looking for some help.
Ive got an 81 f-350 dually 4.9 flatbed. I plan on installing some hydraulics to make it a lift bed.

Im going to a dual optima battery setup under the hood. Do you guys have any suggestion on what model batteries (yellow, red..) Also should i run an isolator? Bigger alternator? General wiring setup?

Any Help would be greatly appreciated. Thanks!
 

Big six Farmer

Well-known member
I would say for sure a large deep cycle battery for the lift, ( Marine, boat stuff )... An isolator system for sure... As far as mounting the Batteries under the hood, that should be easy. Mid 80s Diesel pickups had dual battery mountings, so go for that... Larger Alternator not a bad idea. Look into a newer Ford 3G swap, stupid simple and worth it.
 

pmuller9

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You should run an isolator to be sure the primary battery will always have power to start the engine.
Do you want to be able to charge the second battery from an outside charger?

The yellow top Optima are AGM batteries and work well for both a starter and a deep cycle battery.
The only consideration is you need a charger specifically for AGM batteries when charging externally from the truck.
 
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sixtseventwo4d

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Isolators come in many forms from simple to well, not so simple. A little homework goes a long way. Properly sized cable and connections prevent disappointment.
 

pmuller9

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Isolators come in many forms from simple to well, not so simple. A little homework goes a long way.
That's is why I asked the question "Do you want to be able to charge the second battery from an outside charger?"
That would require a Dual Sensing Isolator.
This thread is part of the "Homework"
 
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sixtseventwo4d

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The separator above serves the purpose of an isolator and 1315-200 allows bi-directional charging as well. Price isn't bad either. I'm not promoting this, it's just something for comparison
 
I like the idea of simplicity. I was hoping my alternator could charge both and have both be active for starting, extra, lights and hydraulics. But im not sure what problem could arise from a simple setup like that. Do you guys have any input on that?
 

pmuller9

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The REDARC Smart Start SBI 12V 100A will charge both batteries when the engine is running and disconnect the second batteries when engine is off.
 
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sixtseventwo4d

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The sure po
I like the idea of simplicity. I was hoping my alternator could charge both and have both be active for starting, extra, lights and hydraulics. But im not sure what problem could arise from a simple setup like that. Do you guys have any input on that?
the sure power 1315-200 will do all of what your asking. It's 200 amp, has it's own logic built in. If you read through the installation steps above it tells what it will do for you. Its not big at all; about twice the size of your typical ford starter solenoid you find mounted on the fender of the older trucks
 

pmuller9

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the sure power 1315-200 will do all of what your asking. It's 200 amp, has it's own logic built in. If you read through the installation steps above it tells what it will do for you. Its not big at all; about twice the size of your typical ford starter solenoid you find mounted on the fender of the older trucks
It's another good choice.
The aux start switch is a nice feature.
 

Cool23

Famous Member
I never buy batteries like Optima. For example the battery in my T Roadster with the inline 6 is a local Aussie brand. It was purchased new in 2005 and has been kept on a battery tender. 16 years old is unheard of when most batteries last 3 to 5 years. I am also reading now many fit up a second battery as stand alone and not a dual system and add solar to charge. May not work with what you intend to do but the tender or solar are both options.
 
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sixtseventwo4d

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Lithium batteries have been making a good showing for reserve power capabilities. Better discharge capacity and faster recharge. initial cost can take your breath. And yes some are really well made ones and some not so. Some of them come with built in BMS. They're NOT suited for freezing temperatures. A little more homework and research.....
 

BigBlue94

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Im from the 4x4 world... Fullsize Bronco.com to be specific. Lots of good writeups over there on the 3G swap, Dual battery swaps, onboard air, etc that may pique your interest. You dont have to even have a bronco or ford to browse or join.

I run dual deep cycle house brand batteries from the local battery supply in my 85 bronco. The second battery is where the factory underhood toolbox was behind the driver headlight. Both batteries are hooked together, no isolator, for 12volts. The PO did it with like 4ga wire. Im running a 200 amp 3G alternator from powermaster. With 3 electric fans and 500w amp, I still pull 14.8 volts at idle.

Before the 200A alternator was installed, I was running I think a 60A 1G. And a mechanical fan, not electric. I was able to power a Karnage offroad welder at idle for a few minutes without an issue.

I recommend upgrading your starter cables, ground cables, and alternator charge wire (if you go to a 3G Alt) to at least 2ga soft strand wire, like from a car audio or welding supply. I prefer the car audio wire and terminals over the welding cables.

I had a yellowtop optima about 2005. Lasted 7-8 years with halogen offroad lights and a big stereo running all night on numerous occasions. Nowadays I dont hear anything good about optimas.

I never run accessories like winches or welders with the engine off.
 

xctasy

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see https://fordsix.com/threads/running-a-desktop-or-tower-computer-in-your-car.72594/

and https://fordsix.com/threads/electrical-drain-revised-130amp-alt-and-twin-batt-soln.72972/


On my 2.5 liter AWD Nissan Stagea WC34, my Toyota Corolla 1300 Hatch, my Ford Explorer XLT 4.0 SOHC, my 1981 Mustang, my three Rav4.1's, I always used an auxiliary marine battery.

On my 1981 3.3 liter Mustang I had a small 12 US gallon fuel tank but did 600 mile per day or night journeys and gas stops werent an option, so used a Marine Battery to ensure I never sparked off a Hunter S Thompson style explosion

IMG_1569_zps63c36d1c.jpg


I used a second battery with a stock alternator to ensure I could run my House computer in my car while out on road inspections. Cool23's advice was great. I refused to use a lower power demand tablet or cell phone because those systems required other power supply requirements.
 
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